Home | Copper Flat Washers - Sealing & Conductive Washers

Copper Flat Washers - Sealing & Conductive Washers

Copper flat washers are valued for their excellent electrical conductivity, thermal performance, and natural sealing properties-making them a preferred choice for hydraulic fittings, electrical connections, and high-temperature applications. Superior Washer & Gasket Corp manufactures copper washers in standard and custom sizes from quality copper stock.

Our ISO 9001:2015 certified facility produces copper flat washers and copper sealing washers from stock inventory and to custom OD, ID, and thickness specifications. All metal washers are made in the U.S.A. with material certifications available for regulated applications.

  • Superior electrical conductivity and thermal properties
  • Excellent natural sealing performance
  • Standard and custom copper flat washer sizes
  • ISO 9001:2015 certified quality assurance
  • Made in the U.S.A.; certifications available

Showing 401–427 of 427 products

SKU ID OD Thickness Material ID TOL OD TOL Quantity

815-73-033

ID 0.233
OD 0.371
Thickness 0.033
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-74-039

ID 0.235
OD 0.407
Thickness 0.039
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-75-036

ID 0.239
OD 0.351
Thickness 0.036
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-76-032

ID 0.247
OD 0.347
Thickness 0.032
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-77-040

ID 0.251
OD 0.407
Thickness 0.04
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-78-025

ID 0.252
OD 0.69
Thickness 0.025
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-79-032

ID 0.253
OD 0.466
Thickness 0.032
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-80-040

ID 0.254
OD 0.4
Thickness 0.04
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-81-032

ID 0.254
OD 0.5
Thickness 0.032
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-82-031

ID 0.254
OD 0.498
Thickness 0.031
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-83-018

ID 0.254
OD 0.502
Thickness 0.018
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-84-018

ID 0.255
OD 0.501
Thickness 0.018
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-85-063

ID 0.258
OD 0.873
Thickness 0.063
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-86-032

ID 0.259
OD 0.437
Thickness 0.032
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-87-072

ID 0.259
OD 0.875
Thickness 0.072
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-88-032

ID 0.261
OD 0.36
Thickness 0.032
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-89-032

ID 0.262
OD 0.619
Thickness 0.032
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-90-040

ID 0.263
OD 0.438
Thickness 0.04
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-91-040

ID 0.264
OD 0.562
Thickness 0.04
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-92-040

ID 0.264
OD 0.565
Thickness 0.04
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-93-033

ID 0.266
OD 0.372
Thickness 0.033
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-94-032

ID 0.266
OD 0.375
Thickness 0.032
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-95-030

ID 0.267
OD 0.437
Thickness 0.03
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-96-049

ID 0.268
OD 0.376
Thickness 0.049
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-97-030

ID 0.268
OD 0.497
Thickness 0.03
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-98-050

ID 0.269
OD 0.496
Thickness 0.05
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

815-99-032

ID 0.28
OD 0.434
Thickness 0.032
Material Copper
ID TOL +-.005
OD TOL +-.005
Quantity

Copper Flat Washer Frequently Asked Questions

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

What are copper flat washers?
Copper flat washers are soft, malleable metal washers manufactured from Copper Alloy 110 (electrolytic tough pitch copper). Their softness makes them ideal for sealing applications where the washer must deform slightly to conform to the mating surface, such as in hydraulic fittings, fuel line connections, and plumbing joints. Superior Washer manufactures copper washers in standard and custom sizes under an ISO 9001:2015 certified QMS.

What are copper flat washers used for?
Copper washers are most commonly used as crush or sealing washers in oil drain plugs, hydraulic fittings, fuel systems, and plumbing connections. When torqued, the soft copper deforms and creates a leak-proof metal-to-metal seal. They are also used as electrical conductors and in applications requiring a soft, sacrificial interface between dissimilar metals.

What copper alloy do you use?
Superior Washer copper flat washers are manufactured from Copper Alloy 110 (C11000), also known as electrolytic tough pitch (ETP) copper. It offers excellent electrical conductivity, thermal conductivity, and malleability.

Can you make custom copper flat washers?
Yes. We produce custom copper washers to your exact OD, ID, and thickness specifications. Contact us via the Quick Quote form or by phone for prototype and production quantities.

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

Copper is just one of the many materials we work with, our full catalog covers metals and plastics for nearly every application. Browse the complete flat washers selection to see what's available.