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Electrical

An extensive range of robust fittings and weatherproof products.

Automotive

Connectivity solutions such as high brackets, busbars, and connector pins.

Power Transmission & Distribution

Connectors & structural components for cutouts, transformers, & substations.

Aerospace

Complex sensor housings & fracture-critical products.

Appliances

Robust castings and assemblies for everyday appliances.

Commercial Hardware

Finished components for commercial & residential hardware applications.

Electronics & Telecom

Precision metal stamped sensors, connectors and cast housings & covers.

Fluid Power

Durable, precision products for high-pressure applications.

Food & Beverage

Handles, leveling pins, flow valves & button housings.

Lighting

Custom housings to fully assembled commercial & industrial light fixtures.

Marine

Durable corrosion-resistant engineered castings and subassemblies.

Medical & Dental

Medical-grade parts for implants, housings, manifolds, and pumps.

Oil & Gas

Custom housings and covers for flow control, pressure valves & meters.

Power Tools

Durable yet lightweight custom metal housings.

Solar

Innovative precision metal stamped parts.

High Pressure Die Casting

High-pressure liquid metal is pressed into a precision metal mold cavity, and then cooled & solidified under pressure.

Ideal for a wide range of applications, including automotive, agricultural, electronics, and medical.

Sand Casting

Castings with complex shapes & inner cavities that are produced in a sand mold

Ideal for parts with complex shapes and inner cavities

Gravity Die Casting

A mold is filled with liquid metal using gravity and cooled and solidified in the mold to obtain a casting

Ideal for parts with complex shapes made with steel, aluminum or magnesium alloys

Investment Casting

A process used to obtain a mold without a parting surface; creates parts with high dimensional & geometric accuracy

Ideal for near-net shaped parts with complex shapes and high precision requirements

Partner Services

Custom Tooling, Machining, Surface Finishing, Special Purpose Machine Design & Development

Precision Metal Stamping

More than 80 presses convert metal sheets into custom parts

Ideal for parts for electronic connectors and microprocessor chips

Swiss Screw Machining

A specialized CNC machine capable of producing extremely small, precise parts

Ideal for complex miniature screws, contact pins & micro-fasteners

Partner Services

Rapid Prototypes, Heat Treating, Automated Assembly

Company History

Learn more about our company milestones.

Plant Locations

Learn more about our global manufacturing facilities.

Company News

See our company announcements and press releases.

Contact Us

Let us know how we can help create a solution for you

Resources

Download catalogs and key product guides.

Global Code of Conduct

Download our Code of Conduct and report violations.

Innovation at Sigma

Purposeful innovation – the continual improvement and innovation of custom-designed and precision-made products and solutions.

Engineered Solutions

Sigma offers solutions for complex product characteristics and technical requirements.

Global Supply Chain Management

U.S.-based supply chain management teams support our customers.

Partner Services

Sigma is a vertically integrated single-source solution provider.

Product Type: Closure Plug

< Products

1/2″ Closure Plug Kit with Wire Nuts

Material: Zinc Die-Cast
Category: Weatherproof
Sub Category: Accessories
Type(s): Closure PlugWire Nut

Closure plugs are used to seal off unused knockouts in weatherproof boxes, extension rings and cluster covers.

  • Includes (3) 1/2″ gray closure plugs and (2) yellow wire nuts
Color Model Number Master Pack Quantity UPC
Gray 18339 10 031857183394
A
0.82
cULus: E121487
Standards: UL 514B, CSA C22.2 No. 18.3-12
65!

WARNING: Cancer and Reproductive Harm – www.P65Warnings.ca.gov.

< Products

3/4″ Closure Plugs

Material: Non-Metallic,Zinc Die-Cast
Category: Weatherproof
Sub Category: Accessories
Type(s): Closure Plug

Closure plugs are used to seal off unused knockouts in weatherproof boxes, extension rings and cluster covers.

Color
Color Model Number
Black CP075B
Gray CP075G
Unpainted CP075
Bronze CP075A
White CP075W
A
1.04
cULus: E121487
Standards: UL 514B, CSA C22.2 No. 18.3-12
65!

WARNING: Cancer and Reproductive Harm – www.P65Warnings.ca.gov.

< Products

1″ Closure Plugs

Material: Zinc Die-Cast
Category: Weatherproof
Sub Category: Accessories
Type(s): Closure Plug

Closure plugs are used to seal off unused knockouts in weatherproof boxes, extension rings and cluster covers.

Color Model Number
Unpainted CP100
cULus: E121487
Standards: UL 514B, CSA C22.2 No. 18.3-12
< Products

1/2″ Closure Plugs

Material: Zinc Die-Cast,Non-Metallic
Category: Weatherproof
Sub Category: Accessories
Type(s): Closure Plug

Closure plugs are used to seal off unused knockouts in weatherproof boxes, extension rings and cluster covers.

Color
Color Model Number
Unpainted CP050
Bronze CP050A
Black CP050B
Gray CP050G
White CP050W
A
0.82
cULus: E121487
Standards: UL 514B, CSA C22.2 No. 18.3-12
65!

WARNING: Cancer and Reproductive Harm – www.P65Warnings.ca.gov.

< Products

1/2″ & 3/4″ Closure Plug Kit

Material: Zinc Die-Cast
Category: Weatherproof
Sub Category: Accessories
Type(s): Closure Plug

Closure plugs are used to seal off unused knockouts in weatherproof boxes, extension rings and cluster covers.

  • Includes 1/2″ and 3/4″ gray closure plugs
Color Model Number Master Pack Quantity UPC
Gray 14050 12 031857140502
cULus: E121487
Standards: UL 514B, CSA C22.2 No. 18.3-12
< Products

1/2″ Closure Plug Kit

Material: Non-Metallic
Category: Weatherproof
Sub Category: Accessories
Type(s): Closure Plug

Closure plugs are used to seal off unused knockouts in weatherproof boxes, extension rings and cluster covers.

  • Includes 1/2″ bronze and white closure plugs
Color Model Number Master Pack Quantity UPC
Bronze, White 14051 12 031857140519
cULus: E121487
Standards: UL 514B, CSA C22.2 No. 18.3-12
65!

WARNING: Cancer and Reproductive Harm – www.P65Warnings.ca.gov.

< Products

1/2″ & 3/4″ Closure Plug Kit

Material: Non-Metallic
Category: Weatherproof
Sub Category: Accessories
Type(s): Closure Plug

Closure plugs are used to seal off unused knockouts in weatherproof boxes, extension rings and cluster covers.

  • Includes 1/2″ gray, bronze and white closure plugs and 3/4″ gray closure plugs
Color Model Number Master Pack Quantity UPC
Gray, Bronze, White 14052 12 031857140528
cULus: E121487
Standards: UL 514B, CSA C22.2 No. 18.3-12
65!

WARNING: Cancer and Reproductive Harm – www.P65Warnings.ca.gov.

< Products

1/2″ Closure Plugs

Material: Zinc Die-Cast
Category: Weatherproof
Sub Category: Accessories
Type(s): Closure Plug

Closure plugs are used to seal off unused knockouts in weatherproof boxes, extension rings and cluster covers.

  • Includes (4) closure plugs
Color
Color Model Number Master Pack Quantity UPC
Gray 14005 30 031857140052
Bronze 14005BR 30 031857340056
White 14005WH 30 031857640057
A
0.82
cULus: E121487
Standards: UL 514B, CSA C22.2 No. 18.3-12
65!

WARNING: Cancer and Reproductive Harm – www.P65Warnings.ca.gov.

< Products

3/4″ Closure Plugs

Material: Zinc Die-Cast
Category: Weatherproof
Sub Category: Accessories
Type(s): Closure Plug

Closure plugs are used to seal off unused knockouts in weatherproof boxes, extension rings and cluster covers.

  • Includes 3/4″ gray closure plugs
Color Model Number Master Pack Quantity UPC
Gray 14007 30 031857140076
A
1.04
cULus: E121487
Standards: UL 514B, CSA C22.2 No. 18.3-12