Sample sourcing studyOctober 21, 2026

Texas sheet metal enclosure suppliers

Make EVS Texas (EVS Metal) lead, Nema Enclosures second source, Guzman and Star fallbacks.

1 week average lead

Houston, TX

Nema Enclosures: The homepage states an average lead time of one week³

32 employees

Houston, TX

Star: LeadIQ estimates about 32 employees as of August 2026⁶

88,000 sq ft about

Houston, TX

Ambox: The facility⁹

Sites in Texas and the US

Headquarters

Also:EVS Texas (EVS Metal)Guzman (United States)

Headquarters
Also:EVS Texas (EVS Metal)Guzman (United States)
1 week average leadHouston, TX Nema Enclosures: The homepage states an average lead time of one week³
32 employeesHouston, TX Star: LeadIQ estimates about 32 employees as of August 2026⁶
88,000 sq ft aboutHouston, TX Ambox: The facility⁹

the five ranked suppliers

1Lead

EVS Texas (EVS

2Second source

Nema Enclosures

3On hold

Ambox

4Fallback

Guzman

5Fallback

Star

The answer

Send the RFQ to all four, starting with EVS Texas (EVS Metal).

Second-source Nema Enclosures: UL508A listed, built in Houston.^1–4

Who gets the RFQ

Four suppliers, led by EVS Texas (EVS Metal).

Lead
EVS Texas (EVS Metal)
It is a contract fabricator with enclosure work and in-house finishing and assembly at a large Texas plant.^{1, 4, 10–11}
24 of 24
Second source
Nema Enclosures
It is a Houston supplier that specializes in custom NEMA-rated electrical enclosures.^12–15
22 of 24
Fallback
Guzman
It is a certified Dallas-area sheet metal shop that lists enclosures and cabinets among its typical jobs.^16–20
20 of 24
Fallback
Star
It is a Houston contract manufacturer whose metal division builds ruggedized enclosures.^{7, 21–23}
20 of 24

Watch

EVS Texas (EVS Metal)'s lead rests on 24 points that come from one website each; without them it scores 0, below Nema Enclosures.^1–2

Next steps

Five steps, starting with the RFQ to EVS Texas (EVS Metal), Nema Enclosures, Guzman and Star.

1
Send enclosure drawings to EVS Texas and Nema Enclosures. Request NEMA types and UL file numbers.
2
Ask Nema Enclosures and Ambox for current ISO 9001 certificates. The ones they posted are expired.
3
Ask Guzman Manufacturing and Star Precision whether they build NEMA-rated or UL-listed enclosures.
4
Audit the EVS Texas Pflugerville and Nema Enclosures Houston plants before awarding the work.
5
Send the RFQ to EVS Texas (EVS Metal), Nema Enclosures, Guzman and Star with the 11 open questions (p. 6).

Scorecard

EVS Texas (EVS Metal) scores 24 of 24; Nema Enclosures 22.

HQWeighted totalof 24; by criterion

1Lead

EVS Texas (EVS

USA

8+8+8

2Second source

Nema Enclosures

Houston

8+6+8

3On hold

Ambox

Houston

6+8+8

4Fallback

Guzman

Dallas

4+8+8

5Fallback

Star

Houston

4+8+8

Enclosures

48 pts

36 pts

24 pts

Certificates

your must-haves first

ISO 9001:2015-compliant process^{1, 4}

+4 more

ISO 9001:2015²⁴

expired Jun 2021 · +2 moreQ5

ISO 9001:2015^25–26

expired Dec 2023Q8

ISO 9001^{18, 27–28}

+5 more

ISO 9001:2015^{7, 29}

+4 more

Stations

To askQ3

NEMA-spec electrical enclosures^{25, 30}Q3

58¹⁸

13 welding machines⁸

another basisQ3

Sheet metal fabrication

48 pts

36 pts

48 pts

Star names the most customers (3); Ambox next (2).

Processes

17processes¹

CNC turret punching, automated laser…

13processes³

cutting, bending

15processes^30–31

sheet metal fabrication, metal…

13processes^{16, 18, 28}

laser cutting, waterjet cutting

20processes^7–8

laser cutting, CNC turret punching

Alloys

steel, stainless steel +1 more¹

powder-coated carbon… +3 more^{3, 13}

316L stainless steel +6 more^{25, 30}

Stainless steel, Aluminum +8 more^{16–17, 19}

mild steel, stainless steel +3 more⁸

Texas location

48 pts

EVS Texas (EVS Metal) leads on plant area at 139,000 sq ft; next Star at 115,000 sq ft.

Plant area

139,000sq ft¹

Houston, Pleasantville Drive²⁴Q7

88,000sq ft⁹

27,000sq ft¹⁶

115,000sq ft²¹

Before award

the condition to meet

Its NEMA and UL panel-shop claims come from its own site only^{1, 4, 10–11}

The ISO certificate on its site has expired^12–15

No UL or NEMA enclosure rating was found.^16–20

No UL or NEMA rating is listed, and its ISO registrar…^{7, 21–23}

Each supplier scored 0–4 per criterion against a published rule; the three asks in your brief count double. The rules, the facts behind every score and the numbered sources are in the online appendix.

Grey: a figure for something else (a group’s, an estimate) or part of an answer

Amber: a change to watch

Q5: an open question for the RFQ

Supplier profiles

EVS Texas (EVS Metal)

EVS Texas (EVS Metal) · evsmetal.com

Lead

Supplier profile · 1 of 3

It is a contract fabricator with enclosure work and in-house finishing and assembly at a large Texas plant.^{1, 4, 10–11}

States an ISO 9001:2015-compliant process.^{1, 4}

In-house machining, welding, powder coating and assembly.^{1, 11}

$90.0M³²

Revenue

FY2025

139,000¹

Plant area

sq ft

ISO 9001:2015-compliant process^{1, 4}

Certificates

+4 more

Privately held³³

Owner

Processes: CNC turret punching, automated laser cutting, automated powder coating · +3 more¹
Alloys: Steel, stainless steel, aluminum¹
Machining and finishing: CNC machining, powder coating, deburring and graining, silk screening · +2 more^{1, 11}

Strengths

Enclosures: Makes NEMA-rated fuse, electrical and junction boxes. States UL 508A panel shop certification^1–2
Sheet metal fabrication: laser cutting, CNC punching, forming, MIG/TIG/robotic welding, hardware insertion, automated powder coating¹
Texas location: plant at 15508 Impact Way, Pflugerville, rebuilt in 2026¹

Watch-outs

Its NEMA and UL panel-shop claims come from its own site only. Ask for the UL file^{1, 4, 10–11}

Company channels

Website: evsmetal.com
RFQ page: evsmetal.com/contact/request-a-quote
Phone: 1-888-9EVSMET; Texas (512) 989-3000

Every score for EVS Texas (EVS Metal), and the facts behind it, is in the online appendix.

Supplier profiles

Nema Enclosures and Guzman

Nema Enclosures

Nema Enclosures · nemaenclosures.com

Second source

Supplier profile · 2 of 3

It is a Houston supplier that specializes in custom NEMA-rated electrical enclosures.^12–15

Quotes through its RFQ page or main line 713-921-2233.^14–15

Announced a new facility in 2024 to add capacity.^12–13

$24.8m³⁶

Revenue

60⁵

People

Processes: Cutting, bending, welding, assembly, sheet metal fabrication · +1 more³

Head office in Houston, TX.³⁸

References

City of Houston wastewater treatment

The company says it is an approved supplier for City of Houston wastewater treatment Levels I and II³⁷

Strengths

Sheet metal fabrication: cutting, bending, welding and assembly in Houston. Low-volume, high-mix, make-to-order work³

Watch-outs

The ISO certificate on its site has expired. Ask for the current one^12–15

Company channels

Website: nemaenclosures.com
RFQ page: nemaenclosures.com/rfq
Phone: 713-921-2233

Every score for Nema Enclosures, and the facts behind it, is in the online appendix.

Guzman

Guzman Manufacturing · gzmetal.com

Fallback

Supplier profile · 3 of 3

It is a certified Dallas-area sheet metal shop that lists enclosures and cabinets among its typical jobs.^16–20

AS9100 certified.^18–19

Works stainless, aluminum, galvanized, inconel and titanium.^{17, 19}

27,000sq ft¹⁶

Plant area

58¹⁸

Production lines

1¹⁷

Named customers

Raytheon, Sanmina, Flextronics, Nortel…

1975^39–40

Founded

Processes: Laser cutting, waterjet cutting, CNC punch press, bend brake and forming, welding · +1 more^{16, 18, 28}

Strengths

Sheet metal fabrication: laser, waterjet, punching, forming, welding. Certificate 60701 runs to 27 JUL 2028^{17, 28}

Watch-outs

No UL or NEMA enclosure rating was found^16–20

Company channels

Website: gzmetal.com
RFQ page: gzmetal.com/contact
Phone: 972-475-3003

Every score for Guzman, and the facts behind it, is in the online appendix.

Risks

Three risks to manage; one applies to every bidder.

Exhibit 1

Three risks to manage before award.

Each risk and the suppliers it affects

	Risk	Affects
1	Ambox’s ISO 9001:2015 certificate expired 2023-12-12, but its page still calls it current.^{26, 41}	Ambox
2	Nema Enclosures’ posted ISO certificate expired 2021-06-14. The expiry of its renewal is not shown.^{24, 42}	Nema Enclosures
3	Steel mill prices rose 20.7% and aluminum 33% from Jan 2025 to Jan 2026.⁴³	Every bidder

Source: nemaenclosures.com [24, 42]; ambox.com [26, 41]; ramsteelco.com [43]

Open questions for the RFQ

Nine questions for the RFQ, by supplier.

Two more questions, for Ambox, are in the online appendix.

For every bidder3 questions

1
Confirm in writing: ISO 9001.
Why: Your brief requires it.
2
Confirm in writing: UL 50 / NEMA enclosure ratings.
Why: Your brief requires it.
3
Ask every bidder how many production lines it would run for the order.
Why: Decides Enclosures, one of the criteria that count double.

EVS Texas (EVS

1 question

4
A registrar-issued ISO 9001 certificate for Pflugerville, the UL panel-shop file number, and which NEMA types it builds.
Why: Needed before award.

Nema Enclosures

3 questions

5
Send the renewed ISO 9001:2015 certificate.
Why: The certificate on file expired Jun 2021.
6
The current ISO 9001 certificate and its expiry, and whether the new powder coat facility is running.
Why: Needed before award.
7
Confirm the floor area of the plant that would build the order.
Why: Decides Texas location, one of the criteria that count double.

Guzman

1 question

10
Whether it builds NEMA-rated or UL-listed enclosures, or only unrated housings.
Why: Decides Enclosures, one of the criteria that count double.

Star

1 question

11
The ISO registrar’s name, and whether its enclosures carry NEMA or UL ratings.
Why: Decides Enclosures, one of the criteria that count double.

Online appendix: the open questions, scoring rules, evidence and sources. On screen only; the PDF has the pages above.

Open questions for the RFQ

Two more questions for Ambox.

Ambox

2 questions

8
Send the renewed ISO 9001:2015 certificate.
Why: The certificate on file expired Dec 2023.
9
Whether it renewed ISO 9001, and whether its enclosures are UL listed.
Why: Decides Enclosures, one of the criteria that count double.

Appendix A · Scoring rules

How the scorecard was scored

Each supplier scores 0–4 per criterion against these rules; p. 8 shows the evidence.

Criterion	Looked at
Enclosures Counts double.	Certificates, Stations
Sheet metal fabrication Counts double.	Processes, Alloys
Texas location Counts double.	Plant area

Each supplier scores 0–4 per criterion, 4 the best. On a cost or risk criterion, 4 means the least cost or risk.

Weighted total: the three asks in your brief count double; the most a supplier can score is 24.

A cell nothing backs is left unscored, never counted as zero.

Appendix A · Evidence

What is behind each score

Score, the facts behind it and their numbered sources (Appendix B, p. 12).

	1Lead EVS Texas (EVS	2Second source Nema Enclosures	3On hold Ambox	4Fallback Guzman	5Fallback Star
Enclosures Counts double.	48 ptsQ3 Makes NEMA-rated fuse, electrical and junction boxes. States UL 508A panel shop certification.^1–2	48 ptsQ3 Q5 Makes UL-listed NEMA 3R and ATEX/IECEx enclosures. Also offers C-UL listed enclosures.^{3, 13}	36 ptsQ3 Q8 Q9 Builds to NEMA specs. Specializes in enclosures for water and wastewater.^{25, 30}	24 ptsQ10 Its typical jobs include enclosures and cabinets. No UL or NEMA rating was found.^{16, 18}	24 ptsQ3 Q11 Builds ruggedized enclosures for defense. No UL or NEMA rating is listed.^{7, 23}
Sheet metal fabrication Counts double.	48 pts Laser cutting, CNC punching, forming, MIG/TIG/robotic welding, hardware insertion, automated powder coating.¹	36 pts Cutting, bending, welding and assembly in Houston. Low-volume, high-mix, make-to-order work.³	48 pts Laser cutting, shearing, punching, forming. Welds to ASME Section IX and AWS B2.1.³¹	48 pts Laser, waterjet, punching, forming, welding. Certificate 60701 runs to 27 JUL 2028.^{17, 28}	48 pts Fleet of 4 lasers, 3 turret punches, 6 press brakes/rollers and 13 welding machines.⁸
Texas location Counts double.	48 pts Plant at 15508 Impact Way, Pflugerville, rebuilt in 2026.¹	48 ptsQ7 Certificate site is 1118 Pleasantville Drive, Houston. All manufacturing is in Houston.²⁴	48 pts Plant at 6040 Telephone Rd, Houston, with over 88,000 sq ft for manufacturing.^{9, 25, 44}	48 pts Facility at 4206 Industrial St, Rowlett, in the Dallas area.^{18, 39}	48 pts Metal division at 5410 Brystone Drive, Houston, a 50,000 sq ft plant.^21–22
Weighted total	248+8+8	228+6+8	226+8+8	204+8+8	204+8+8

Appendix A · Method and long list

How the study was run

On October 21, 2026, the study read 178 web pages in 40 min and checked 23 findings on a second website.

Exhibit 2

36 found, 5 ranked.

Companies at each stage

36Found

27Fit the brief

19Researched in depth

5Ranked

Company	Type	Home	Reason
Ranked (5)
EVS Texas (EVS Metal)¹	Precision sheet…	US	Lead: texas facility in Pflugerville makes NEMA-rated electrical enclosures and complex welded enclosures. Site…
Nema Enclosures³⁸	Custom…	Houston, US	Second source: says it manufactures NEMA enclosures in Texas, with UL508A listing and C-UL listing, in carbon steel…
Ambox Limited²⁵	Electrical…	Houston, US	On hold.
Guzman Manufacturing¹⁸	Component…	Dallas, US	Fallback: sheet metal and component maker in Rowlett, TX (Dallas area) with ISO 9001 and AS9100 certification. Site…
Star Precision⁷	Contract…	Houston, US	Fallback: houston, TX contract manufacturer with ISO 9001:2015 certification. Its sheet metal line makes…
Researched in depth, not ranked (14)
AmeriStar Mfg.⁴⁵	Custom…	US	Makes NEMA and UL enclosures, but Texas location and ISO 9001 are not confirmed.
Bison ProFab⁴⁶	Custom NEMA…	US	Makes UL-listed NEMA enclosures, but the Texas location is not confirmed.
Enclosure Fabrication⁴⁷	Custom sheet…	Houston, US	Houston-area enclosure shop with ETL listing. It is young, its addresses conflict, and no ISO claim was found.
EVS (Engineered Vehicle/Sheet metal group, as named on source)⁴⁸		US	EVS group page. Its Texas plant is covered by the EVS Texas entry.
EVS Metal³²	Precision sheet…	Pflugerville, US	Duplicate of EVS Texas in Pflugerville, which is already in the cut.
IndustLabs⁴⁹	Custom steel…	US	Garland panel and enclosure shop. It claims UL status and commits to ISO, but no certificate was found.

Appendix A · Method and long list · continued

How the study was run

Company	Type	Home	Reason
Researched in depth, not ranked (14), continued
Larson Electronics⁵⁰	Custom electrical…	US	Builds NEMA enclosures in Kemp. Sources disagree on its plant size, and its ISO certificate could not be opened.
Maysteel Industries⁵¹	Data center racks…	US	Its Garland plant is ISO certified. But its UL enclosure file sits at the Wisconsin headquarters, and it was sold this year.
Partners Metal Fab (Partners Metalfab / Metal Craft / Robbins Metalfab)⁵²	Houston electrical…	Houston, US	Says it makes UL-listed NEMA enclosures, but no ISO certificate or UL file number was found.
Red River Precision⁵³	Custom sheet…	Austin, US	Texas shop (Round Rock) doing sheet metal and custom metal fabrication, with enclosures in its news posts…
ReNEW Manufacturing Solutions⁵⁴	Custom fabricator…	Austin, US	Austin fabricator on the FAB 40 list, but its scope and certifications are unverified.
Texas Contract Manufacturing Group⁵⁵		US	Austin sheet metal group, but no enclosure work and no clear ISO 9001 claim.
Theriot, Inc.⁵⁶	Listed with an ISO…	US	Claims ISO 9001 and NEMA/UL listing, but the source is unclear and Texas is not shown.
Tripar Inc.⁵⁷	Turnkey sheet…	El Paso, US	El Paso sheet metal maker that lists enclosures among its parts and runs 100 to 1M+ units. Its catalog is mostly…
Fit the brief, not researched (8)
Austin Waterjet, Inc.⁵⁸	Precision CNC…	Austin, US	No homepage was given, so we could not open its own site. Brief lists CNC sheet metal parts in Austin, TX, not…
El Campo Sheet Metal, LLC⁵⁹	Custom…	El Campo, US	No homepage was given, so we could not verify on its own site. Listing places it in El Campo, Texas and mentions…
Eldred Sheet Metal Works⁶⁰	Custom sheet…	US	No homepage was given, so we could not verify. Listing mentions enclosures and ISO 9001:2015 with NEMA/UL…
H&S Manufacturing Co.⁶¹	Precision sheet…	US	No homepage was given, so we could not verify. Listing says precision sheet metal fabrication including enclosures and…
Myrmidon Corp⁶²	Houston shop…	Houston, US	Houston shop that lists custom sheet metal enclosures and sheets up to 60 x 120 in. No website was given, so we…
Southeast Texas Industries, Inc.⁶⁰	Custom sheet…	US	No homepage was given, so we could not verify. Listing describes custom sheet metal enclosures and hoods, but…
Texas Toolmakers, Inc.⁶³	Privately owned…	San Antonio
Thompson-Mathis Metal Manufacturing Company⁶⁴	Fabrication…	Dallas, US	No homepage was given, so we could not open its own site. Only a directory listing; capabilities and certifications not…
Did not fit the brief (9)
5M CNC⁶⁵	Turn-key custom…	Dallas, US	General metal fabrication and powder coating shop in Kaufman, TX. Site shows laser cutting and press brake…
Alpine Sheet Metal Systems⁶⁶	Custom sheet…	Dallas, US	DFW commercial contractor for architectural metal, roofing and flashing. Says it does not sell raw sheet metal. No…
Burke and Pruski Metal Fab and Powder Coating⁶⁷	Metal fabrication…	San Antonio	CNC cutting, stamping and powder coating shop in Elmendorf, TX (San Antonio area). No ISO 9001 claim and…
Dominguez Sheet Metal Works, Inc.⁶⁸	El Paso sheet…	El Paso, US	El Paso shop focused on HVAC, ductwork, flashing and welding. Its site shows no enclosure work.

Appendix A · Method and long list · continued

How the study was run

Company	Type	Home	Reason
Did not fit the brief (9), continued
Efficient AC, Electric & Plumbing (Efficient Texas)⁶⁹	Makes sheet metal…	Austin, US	Austin, TX sheet metal shop, but its work is mainly HVAC ductwork and fittings. No ISO 9001 or UL/NEMA claim on…
EP Fabtech⁷⁰	El Paso metal…	El Paso, US	El Paso maker of metal roof and wall panels, trims, flashings and ACM panels. Its site names no enclosure work, no ISO…
Hot Shot Laser⁷¹	Rapid contract…	Salado, US	Rapid contract cutting and forming shop in Salado, TX. No ISO 9001 claim and no enclosure or NEMA/UL rating seen…
Performance Sheet Metal (McAllen)⁷²	Custom sheet…	McAllen, US	Site says it serves the USA from Washington State, with a McAllen landing page. It lists general fabrication for…
Precision Metal Services⁷³	Describes itself…	Austin, US	Austin welding and structural steel shop. Its work is generator platforms, steel framing and field welding, not…

Appendix B · Sources

Numbered sources

Superscript numbers in the text and bracketed numbers in source lines point here.

1
EVS Metal Texas metal fabrication page — evsmetal.com, 2026-08-28
evsmetal.com/texas-metal-fabrication
(4) HRB 1003 10′ 110 Ton Press Brake
2
evsmetal.com
evsmetal.com/sheet-metal-products
UL 508A panel shop certification, and NEMA-rated enclosure manufacturing
3
Nema Enclosures homepage — nemaenclosures.com, 2026-10-21
nemaenclosures.com
Manufactured in Texas. UL508A Listed. Built to Spec.
4
njmep.org
njmep.org/about-us/manufacturing-in-nj/company/evs-metal
Our four American metal manufacturing facilities are ISO:9001-2015 certified and conveniently located in northern New Jersey, Texas
5
pitchbook.com
pitchbook.com/profiles/company/241421-77
Nema Enclosures has 60 total employees.
6
leadiq.com
leadiq.com/c/star-precision-lp/5a1d9ce423000054008cb4ae
As of August 2026, Star Precision, LP's annual revenue is estimated to be $25M - $50M.
7
star-precision.com
star-precision.com
Certified quality management system covering every process across both Houston, Texas facilities.
8
star-precision.com
star-precision.com/services/metal-fabrication
Laser cutting, NC punching, forming, rolling, hardware installation and finishing, up to 60 x 120 in sheet.
9
ambox.com
ambox.com/ambox-history
over 88,000 square feet is utilized for manufacturing automotive, oil field, medical, government, and various other metal products
10
EVS Metal About page — evsmetal.com, 2026-10-21
evsmetal.com/our-company
EVS Metal was founded in 1994 by Joe Amico and Scott Berkowitz

11
mapquest.com
mapquest.com/us/texas/evs-metal-fabrication-texas-353267754
offers services such as CNC machining, welding, finishing, and assembly integration
12
Nema Enclosures Manufacturing LinkedIn page — linkedin.com, 2026-10-21
linkedin.com/company/nema-enclosures
Rob has invited SME Houston to return at a future date to see the addition of a complete automated powder coating line.
13
Nema Enclosures About Us page — nemaenclosures.com, 2026-10-21
nemaenclosures.com/about-us
Nema Enclosures was founded in 1987 by a NASA employee who began custom fabricating enclosures
14
nemaenclosures.com
nemaenclosures.com/contact-us
713-921-2233
15
thefabricator.com
thefabricator.com/directory/showroom/nema-enclosures
Phone: 713-921-2233
16
Guzman Manufacturing home page — gzmetal.com, 2026-10-21
gzmetal.com
Typical fabrication jobs include, but are not limited to: Electronics Chassis & Frames; Enclosures, Assemblies, Cabinets & Panels; Brackets; Prototypes; Bus bars; Housings; Face Plates
17
Guzman Manufacturing Capabilities page — gzmetal.com, 2026-10-21
gzmetal.com/capabilities
Food Service · Telecom · Printing · Conveyor Systems · Raytheon · Sanmina · Flextronics · Nortel · Alcatel/Lucent · Various Defense Contractors
18
Guzman Manufacturing CNC Punch Press page — gzmetal.com, 2026-10-21
gzmetal.com/services/cnc-punch-press
ISO 9001 & AS9100 Certified
19
manta.com
manta.com/c/mmff00m/guzman-manufacturing-inc
ISO 9001 & AS9100 Certified -Dallas/Ft. Worth Area
20
yelp.com
yelp.com/biz/guzman-mfg-rowlett
(972) 475-3003 · Get Directions · 4206 Industrial St Rowlett, TX 75088

Appendix B · Sources · continued

Numbered sources

21
star-precision.com
star-precision.com/about/facility
Our second facility at 11236 Brittmoore Park Drive offers electronics, machining and electro-mechanical services.
22
linkedin.com
linkedin.com/company/starprecisionlp
Our Headquarter located at 5410 Brystone Drive in Houston, Texas houses our Metal Fabrication division
23
manta.com
manta.com/c/mm6353f/star-precision-fabricating-ltd
Star services the electronics, medical, oil and gas, consumer, industrial, semiconductor, telecommunications, biotechnology defense and other industries.
24
nemaenclosures.com
nemaenclosures.com/wp-content/uploads/2018/07/Nema-185027-IA-Final-Cert.pdf
has been found to conform to the Quality Management System standard: ISO 9001:2015
25
ambox.com
ambox.com/industrial-enclosures
petrochemical, oil and gas, marine, manufacturing
26
ambox.com
ambox.com/wp-content/uploads/2021/01/Ambox-Limited-35898-9001-2020-Final-QR.pdf
Initial certification date: 20 November, 1997
27
gzmetal.com
gzmetal.com/quality/iso-9001-certification
Guzman Manufacturing is a Dallas sheet metal facility holding ISO 9001:2008, AS9100, MBE and HUB certifications
28
gzmetal.com
gzmetal.com/wp-content/uploads/2025/07/Certificate-AS91002016-techn.-equiv.-to-EN91002018-_-JISQ91002016-Guzman-Manufacturing_-Inc.-461493-104209126-1.pdf
Effective Date: 28 JUL 2025 Expiration Date: 27 JUL 2028
29
star-precision.com
star-precision.com/about/quality-certifications
IPC/WHMA-A-620 for cable and wire harnesses, and J-STD-001 for soldering.
30
ambox.com
ambox.com/custom-enclosures
Ambox manufactures to NEMA specs on electrical enclosures with custom fabrication

31
ambox.com
ambox.com/about
Since 1953, Ambox Limited has advanced into a custom contract metal manufacturer
32
EVS Metal FAB 40 press release (PR Newswire via PRWeb) — prweb.com, 2026-06-16
prweb.com/releases/evs-metal-ranks-no-21-on-2026-fab-40-list-marking-17th-consecutive-year-among-leading-us-metal-fabricators-302796416.html
based on 2025 reported revenue of more than $90 million, representing a more than 40% increase year over year
33
EVS Metal Frequently Asked Questions — evsmetal.com, 2026-08-28
evsmetal.com/metal-fabrication-faq
Yes, all four of EVS's metal fabrication facilities are ISO 9001:2015 certified.
34
streetinsider.com
streetinsider.com/Press+Releases/EVS+Metal+Ranks+No.+21+on+2026+FAB+40+List,+Marking+17th+Consecutive+Year+Among+Leading+U.S.+Metal+Fabricators/26649979.html
ranking No. 21 among the country's leading metal fabricating operations
35
EVS Metal blog: 2026 FAB 40 ranking and what it means for OEMs — evsmetal.com
evsmetal.com/2026/06/what-evs-metals-fab-40-ranking-means-oems-industrial-buyers
on 2025 revenue of more than $90 million
36
zoominfo.com
zoominfo.com/c/nema-enclosures/87689497
Manufacturing · Texas, United States · 51-200 Employees
37
nemaenclosures.com
nemaenclosures.com/about-us/industries-served/wastewater
All electrical enclosures are manufactured in compliance with NEMA standards; are UL listed, and/or IP rated.
38
nemaenclosures.com
nemaenclosures.com/blog
Nema Enclosures has produced thousands of custom enclosures that are UL508A listed
39
Guzman Manufacturing About Us page — gzmetal.com, 2026-10-21
gzmetal.com/about-us
Our 27,000 square foot facility is equipped with the machinery and know-how to handle any task, large or small.
40
scrapmonster.com
scrapmonster.com/company/guzman-manufacturing-inc/88544
In business since 1975, GUZMAN MFG.
41
ambox.com
ambox.com/quality-iso
Current ISO 9001 Certificate

Appendix B · Sources · continued

Numbered sources

42
nemaenclosures.com
nemaenclosures.com/nema-enclosures-mfg-awarded-iso-90012015-re-certification-as-a-seal-of-quality-standard
successful re-certification to the ISO 9001:2015 standard and have been recommended for continued certification for the next 3 years.
43
ramsteelco.com
ramsteelco.com/blogs/news/how-steel-aluminum-tariffs-are-affecting-prices-in-2026-and-how-to-keep-your-project-on-budget
steel mill products rose 20.7% and aluminum mill shapes rose 33%
44
yelp.com
yelp.com/biz/ambox-limited-houston
6040 Telephone Rd · Houston, TX 77087 · Golfcrest/Belfort/Reveille
45
thomasnet.com
thomasnet.com/suppliers/usa/sheet-metal-enclosures-26081349
46
bisonprofab.com
bisonprofab.com/oil-gas-production-enclosure.htm
47
enclosurefabrication.com
enclosurefabrication.com/centerpoint-energy-approved-vendor
48
evsmetal.com
evsmetal.com/2026/06/sheet-metal-fabrication-data-center-infrastructure
49
industlabs.com
industlabs.com/steel-enclosures
We are UL certified and can produce any enclosure type from NEMA12, NEMA 3R, NEMA 4, & NEMA 4X to blast proof.
50
larsonelectronics.com
larsonelectronics.com/news/4553/custom-electrical-enclosures-manufactured-in-texas-for-industrial-applications
Common options include carbon steel, aluminum, 304 stainless steel and 316 stainless steel
51
maysteel.com
maysteel.com/industries/data-center-products
52
partnersmetalfab.com
partnersmetalfab.com/ul-listed-type-4-4x-12-enclosures
Choose from durable powder coating in a range of colors
53
redriverprec.com
redriverprec.com/metal-fabrication-news-corner/precision-sheet-metal-fabrication-tailored-solutions-from-austin-and-beyond
54
renewmfgsol.com
renewmfgsol.com/blog/2025-fab-40-list
55
tcmgco.com
tcmgco.com/services-and-capabilities/precision-sheet-metal-fabrication

56
thomasnet.com
thomasnet.com/suppliers/southern-texas/all-cities/stainless-steel-enclosures-96025473
57
triparinc.com
triparinc.com/sheet-metal-fabrication-el-paso-tx
From 100 to 1M+ unit production capabilities.
58
thomasnet.com
thomasnet.com/suppliers/southern-texas/all-cities/precision-sheet-metal-fabrication-74361007
59
thomasnet.com
thomasnet.com/suppliers/southern-texas/all-cities/carbon-steel-enclosures-96219280
60
thomasnet.com
thomasnet.com/suppliers/southern-texas/all-cities/custom-metal-enclosures-95929006
61
thomasnet.com
thomasnet.com/suppliers/northern-texas/all-cities/sheet-metal-fabrication-74351008
62
myrmcorp.com
myrmcorp.com/products/sheet-metal-enclosures
63
yellowpages.com
yellowpages.com/austin-tx/sheet-metal-fabricators
64
clutch.co
clutch.co/logistics/fabrication/steel/texas
65
5mcnc.com
5mcnc.com/custom-laser-cutting
66
alpinesheetmetalsystems.com
alpinesheetmetalsystems.com/building-sheet-metal
67
burkeandco.com
burkeandco.com/cnc-cutting-forming
68
dominguezsheetmetal.com
dominguezsheetmetal.com
69
efficienttexas.com
efficienttexas.com/sheetmetal
70
epfabtechmetals.com
epfabtechmetals.com
71
hotshotlaser.com
hotshotlaser.com
72
performancesheetmetal.com
performancesheetmetal.com/mcallen/fabrication-mcallen-tx
73
pmswelding.com
pmswelding.com/pages/data-center-welding

Make EVS Texas (EVS Metal) lead, Nema Enclosures second source, Guzman and Star fallbacks.

Send the RFQ to all four, starting with EVS Texas (EVS Metal).

Who gets the RFQ

Next steps

EVS Texas (EVS Metal) scores 24 of 24; Nema Enclosures 22.

EVS Texas (EVS Metal)

Strengths

Watch-outs

Recent news

Company channels

Nema Enclosures and Guzman

References

Strengths

Watch-outs

Recent news

Company channels

Strengths

Watch-outs

Company channels

Three risks to manage; one applies to every bidder.

Nine questions for the RFQ, by supplier.

Two more questions for Ambox.

How the scorecard was scored

What is behind each score

How the study was run

How the study was run

How the study was run

Numbered sources

Numbered sources

Numbered sources