Home | Metric Copper Washers - Sealing & Conductive Flat Washers

Metric Copper Washers - Sealing & Conductive Flat Washers

Metric copper washers are valued for their superior sealing performance, electrical conductivity, and corrosion resistance in metric fastener applications including hydraulic fittings, plumbing connections, and electrical assemblies. Superior Washer & Gasket Corp supplies metric copper washers in standard DIN and ISO sizes and produces custom metric copper sealing washers to your specifications.

As an ISO 9001:2015 certified metal washer manufacturer, we maintain inventory of metric copper washers for fast delivery and offer custom stamping for non-standard metric sizes. All products are made in the U.S.A. with complete material traceability.

  • Metric copper washers for hydraulic and sealing applications
  • DIN and ISO standard sizes in stock
  • Custom metric copper sealing washers available
  • ISO 9001:2015 certified manufacturing
  • Made in the U.S.A.

Showing 351–400 of 400 products

SKU ID (MM) OD (MM) Thickness (MM) Material ID MM TOL OD MM TOL Quantity

175-2503

ID (MM) 17.399
OD (MM) 23.8
Thickness (MM) 3.175
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2504

ID (MM) 17.399
OD (MM) 37.998
Thickness (MM) 2.362
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2505

ID (MM) 17.526
OD (MM) 22.123
Thickness (MM) 1.575
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2506

ID (MM) 17.526
OD (MM) 23.8
Thickness (MM) 3.175
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2507

ID (MM) 17.526
OD (MM) 25.4
Thickness (MM) 1.575
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2508

ID (MM) 17.526
OD (MM) 38.125
Thickness (MM) 2.388
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2509

ID (MM) 17.551
OD (MM) 25.4
Thickness (MM) 1.575
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2510

ID (MM) 17.653
OD (MM) 22.276
Thickness (MM) 0.787
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2511

ID (MM) 18.059
OD (MM) 24.638
Thickness (MM) 1.27
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2512

ID (MM) 18.288
OD (MM) 26.924
Thickness (MM) 2.362
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2513

ID (MM) 19.101
OD (MM) 25.857
Thickness (MM) 1.575
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2514

ID (MM) 19.126
OD (MM) 23.774
Thickness (MM) 0.864
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2515

ID (MM) 19.177
OD (MM) 28.575
Thickness (MM) 1.6
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2516

ID (MM) 19.355
OD (MM) 25.806
Thickness (MM) 2.032
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2517

ID (MM) 19.482
OD (MM) 33.325
Thickness (MM) 2.134
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2518

ID (MM) 19.507
OD (MM) 26.873
Thickness (MM) 1.27
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2519

ID (MM) 19.507
OD (MM) 33.325
Thickness (MM) 2.362
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2520

ID (MM) 19.533
OD (MM) 38.024
Thickness (MM) 0.813
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2521

ID (MM) 19.914
OD (MM) 38.151
Thickness (MM) 1.27
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2522

ID (MM) 20.295
OD (MM) 24.943
Thickness (MM) 0.991
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2523

ID (MM) 20.295
OD (MM) 25.298
Thickness (MM) 2.388
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2524

ID (MM) 20.447
OD (MM) 25.73
Thickness (MM) 1.27
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2525

ID (MM) 20.625
OD (MM) 50.8
Thickness (MM) 3.175
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2526

ID (MM) 20.726
OD (MM) 27.737
Thickness (MM) 0.254
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2527

ID (MM) 20.726
OD (MM) 37.287
Thickness (MM) 3.277
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2528

ID (MM) 21.006
OD (MM) 26.518
Thickness (MM) 1.27
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2529

ID (MM) 22.2
OD (MM) 26.721
Thickness (MM) 1.575
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2530

ID (MM) 22.225
OD (MM) 26.187
Thickness (MM) 0.813
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2531

ID (MM) 22.301
OD (MM) 31.75
Thickness (MM) 1.6
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2532

ID (MM) 22.454
OD (MM) 32.487
Thickness (MM) 0.813
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2533

ID (MM) 22.606
OD (MM) 28.575
Thickness (MM) 1.575
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2534

ID (MM) 22.708
OD (MM) 32.487
Thickness (MM) 1.549
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2535

ID (MM) 22.911
OD (MM) 32.969
Thickness (MM) 3.175
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2536

ID (MM) 23.012
OD (MM) 60.325
Thickness (MM) 3.251
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2537

ID (MM) 24.257
OD (MM) 28.575
Thickness (MM) 1.6
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2538

ID (MM) 24.308
OD (MM) 28.626
Thickness (MM) 1.575
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2539

ID (MM) 25.451
OD (MM) 34.976
Thickness (MM) 1.6
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2540

ID (MM) 25.476
OD (MM) 38.049
Thickness (MM) 3.175
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2541

ID (MM) 25.527
OD (MM) 31.775
Thickness (MM) 0.762
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2542

ID (MM) 25.857
OD (MM) 33.274
Thickness (MM) 1.6
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2543

ID (MM) 26.975
OD (MM) 63.5
Thickness (MM) 3.251
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2544

ID (MM) 27.0
OD (MM) 39.675
Thickness (MM) 1.575
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2545

ID (MM) 29.464
OD (MM) 47.65
Thickness (MM) 2.388
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2546

ID (MM) 30.302
OD (MM) 35.712
Thickness (MM) 0.483
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2547

ID (MM) 31.648
OD (MM) 38.405
Thickness (MM) 0.813
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2548

ID (MM) 31.775
OD (MM) 38.151
Thickness (MM) 1.651
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2549

ID (MM) 32.664
OD (MM) 35.687
Thickness (MM) 0.813
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2550

ID (MM) 34.849
OD (MM) 41.3
Thickness (MM) 1.575
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2551

ID (MM) 35.382
OD (MM) 42.926
Thickness (MM) 1.575
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

175-2552

ID (MM) 38.989
OD (MM) 47.498
Thickness (MM) 0.787
Material Copper
ID MM TOL 0.127
OD MM TOL 0.127
Quantity

Metric Copper Washer Frequently Asked Questions

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

What are metric copper washers?
Metric copper washers are flat sealing and conductive washers dimensioned in millimeters for use with metric fasteners. Superior Washer manufactures metric copper washers to DIN and ISO standard sizes and custom metric dimensions, with over 400 configurations in stock. Copper's softness and malleability make metric copper washers ideal for creating leak-proof seals in metric hydraulic fittings, plumbing connections, and fuel systems.

What are metric copper washers used for?
Metric copper washers are most commonly used as crush or sealing washers in metric hydraulic fittings, drain plugs, banjo bolt connections, and plumbing joints where a leak-proof metal-to-metal seal is required. They are also used in electrical assemblies as conductive spacers and in applications requiring a soft, non-galling interface between metric fasteners and mating surfaces.

What size range are your metric copper washers available in?
Our metric copper catalog covers ID sizes from approximately 1.9 mm through 20.7 mm and OD sizes from approximately 3.9 mm through 38.2 mm, in thicknesses from 0.127 mm through 3.28 mm. This range supports common metric hydraulic and plumbing fitting sizes across M3 through M20 and beyond.

Can you produce custom metric copper washers?
Yes. We manufacture custom metric copper sealing washers to your exact millimeter OD, ID, and thickness specifications. Contact us via the Quick Quote form or call NY (631) 273-8282 or SC (803) 366-3250.

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

Need copper in imperial sizing instead? We also stock copper and other materials in SAE and USS dimensions. Browse the full flat washers catalog to compare all sizing and material options.