Home | Phenolic Flat Washers - Hard, Heat-Resistant Insulating Washers

Phenolic Flat Washers - Hard, Heat-Resistant Insulating Washers

Phenolic flat washers are made from thermoset phenolic resin, offering excellent electrical insulation, hardness, and heat resistance-making them a reliable non-metallic washer for electrical equipment, circuit boards, and industrial applications with moderate temperature exposure. Superior Washer & Gasket Corp produces phenolic washers in standard and custom sizes.

As an ISO 9001:2015 certified specialty washer manufacturer, we supply phenolic washers alongside fiberglass, Kapton, mica, and other high-performance insulating washers-all made in the U.S.A. to your precise OD, ID, and thickness requirements.

  • Thermoset phenolic for hardness and electrical insulation
  • Good heat resistance for industrial applications
  • Standard and custom phenolic washer configurations
  • ISO 9001:2015 certified manufacturing
  • Made in the U.S.A.

Showing 51–100 of 243 products

SKU ID OD Thickness Material ID TOL OD TOL Quantity

440-144-062

ID 0.253
OD 0.687
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-145-031

ID 0.253
OD 0.562
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-146-062

ID 0.253
OD 0.625
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-147-031

ID 0.253
OD 0.687
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-148-062

ID 0.253
OD 0.75
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-149-062

ID 0.253
OD 0.812
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-15-016

ID 0.067
OD 0.125
Thickness 0.016
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-150-062

ID 0.253
OD 0.875
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-151-031

ID 0.253
OD 1.062
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-152-062

ID 0.253
OD 1.437
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-153-031

ID 0.26
OD 0.375
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-154-031

ID 0.26
OD 0.437
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-155-031

ID 0.26
OD 0.5
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-156-062

ID 0.26
OD 0.562
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-157-031

ID 0.26
OD 0.687
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-158-125

ID 0.26
OD 0.73
Thickness 0.125
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-159-031

ID 0.26
OD 0.75
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-16-016

ID 0.073
OD 0.125
Thickness 0.016
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-160-031

ID 0.26
OD 0.875
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-161-031

ID 0.26
OD 1.5
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-162-031

ID 0.281
OD 0.42
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-163-031

ID 0.281
OD 0.5
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-164-062

ID 0.281
OD 0.54
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-165-062

ID 0.281
OD 0.625
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-165M-031

ID 0.282
OD 0.625
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-166-031

ID 0.281
OD 0.75
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-167-031

ID 0.312
OD 0.437
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-168-031

ID 0.312
OD 0.544
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-169-062

ID 0.312
OD 1.0
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-17-016

ID 0.078
OD 0.156
Thickness 0.016
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-170-062

ID 0.312
OD 1.25
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-171-031

ID 0.317
OD 0.5
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-172-031

ID 0.317
OD 0.515
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-173-031

ID 0.317
OD 0.562
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-174-031

ID 0.317
OD 0.6
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-175-031

ID 0.317
OD 0.625
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-176-062

ID 0.317
OD 0.687
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-177-031

ID 0.317
OD 0.75
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-178-062

ID 0.328
OD 0.562
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-178M-062

ID 0.328
OD 0.569
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-179-031

ID 0.375
OD 0.5
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-18-031

ID 0.078
OD 0.187
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-180-045

ID 0.375
OD 0.656
Thickness 0.045
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-181-031

ID 0.375
OD 0.875
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-182-062

ID 0.375
OD 1.0
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-183-062

ID 0.385
OD 0.5
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-184-031

ID 0.385
OD 0.625
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-185-062

ID 0.385
OD 0.687
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-186-031

ID 0.385
OD 0.75
Thickness 0.031
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

440-187-062

ID 0.385
OD 1.0
Thickness 0.062
Material Phenolic
ID TOL +-.005
OD TOL +-.005
Quantity

Phenolic Flat Washer Frequently Asked Questions

Below are answers to some of the most common questions about phenolic flat washers.

What are phenolic flat washers?
Phenolic flat washers are manufactured from phenol-formaldehyde resin laminate (Bakelite or equivalent), one of the oldest and most established electrical insulating materials. Phenolic is available in paper-base (XX, XXX, XXXP), cotton-base (C, CE, LE), and glass-base (G10) grades, each offering different balances of electrical, mechanical, and thermal properties.

What are phenolic washers used for?
Phenolic washers are used as electrical insulators in switchgear, relay panels, transformers, motors, and terminal blocks. They are also used as mechanical spacers in assemblies where a rigid, non-conductive washer is required. Phenolic is harder and more rigid than most thermoplastic washer materials, which makes it suitable for high-compression applications.

What phenolic grades do you stock?
Superior Washer manufactures phenolic flat washers in XX, XXX, and CE grades depending on the required electrical and mechanical properties. Contact us to specify the grade needed for your application.

Can you make custom phenolic flat washers?
Yes. We manufacture custom phenolic washers to your OD, ID, and thickness specifications. Contact us via the Quick Quote form or by phone.

Are your phenolic flat washers made in the USA?
Yes. All phenolic flat washers are manufactured in the United States under our ISO 9001:2015 certified Quality Management System. Material certifications are available upon request.

Phenolic is one of several rigid insulating materials we manufacture. View our complete flat washers lineup to compare all the options available.