Home | 301/302/304 Stainless Steel Flat Washers - Corrosion-Resistant Washers

301/302/304 Stainless Steel Flat Washers - Corrosion-Resistant Washers

Stainless steel flat washers in 301, 302, and 304 grades provide excellent corrosion resistance, strength, and aesthetic quality for fastener assemblies across marine, food processing, pharmaceutical, architectural, and industrial applications. Superior Washer & Gasket Corp manufactures 300-series stainless steel flat washers in a broad range of standard and custom sizes.

Our ISO 9001:2015 certified manufacturing facility supplies stainless steel washers from stock inventory and produces custom stainless flat washers with tight dimensional tolerances. All stainless steel washers are made in the U.S.A. with material certifications available for regulated applications.

  • 301, 302, and 304 stainless steel grades available
  • Broad standard size inventory for fast delivery
  • Custom stainless steel flat washers to specification
  • ISO 9001:2015 certified quality assurance
  • Made in the U.S.A.; certifications available

Showing 3851–3900 of 4,985 products

SKU ID OD Thickness Material ID TOL OD TOL Quantity

300-397-062

ID 0.138
OD 0.392
Thickness 0.062
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-398-010

ID 0.138
OD 0.439
Thickness 0.01
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-399-005

ID 0.138
OD 0.5
Thickness 0.005
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-400-031

ID 0.14
OD 0.328
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4000-031

ID 0.469
OD 1.625
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4000-060

ID 0.469
OD 1.625
Thickness 0.06
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4000-090

ID 0.469
OD 1.625
Thickness 0.09
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4000-125

ID 0.469
OD 1.625
Thickness 0.125
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4001-031

ID 0.469
OD 1.75
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4001-060

ID 0.469
OD 1.75
Thickness 0.06
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4001-090

ID 0.469
OD 1.75
Thickness 0.09
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4001-125

ID 0.469
OD 1.75
Thickness 0.125
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4002-031

ID 0.469
OD 1.875
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4002-060

ID 0.469
OD 1.875
Thickness 0.06
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4002-090

ID 0.469
OD 1.875
Thickness 0.09
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4002-125

ID 0.469
OD 1.875
Thickness 0.125
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4003-031

ID 0.469
OD 2.0
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4003-060

ID 0.469
OD 2.0
Thickness 0.06
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4003-090

ID 0.469
OD 2.0
Thickness 0.09
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4003-125

ID 0.469
OD 2.0
Thickness 0.125
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-401-010

ID 0.14
OD 0.375
Thickness 0.01
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4010-046

ID 0.262
OD 0.687
Thickness 0.046
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4011-075

ID 0.344
OD 0.688
Thickness 0.075
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4012-005

ID 0.379
OD 0.747
Thickness 0.005
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4015-059

ID 0.754
OD 1.0
Thickness 0.059
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4016-025

ID 0.091
OD 0.187
Thickness 0.025
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4018-020

ID 0.131
OD 0.231
Thickness 0.02
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4019-010

ID 0.147
OD 0.275
Thickness 0.01
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-402-031

ID 0.14
OD 0.377
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4020-061

ID 0.157
OD 0.373
Thickness 0.061
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4021-030

ID 0.252
OD 0.374
Thickness 0.03
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4023-033

ID 0.251
OD 0.437
Thickness 0.033
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4024-062

ID 0.202
OD 0.468
Thickness 0.062
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4026-120

ID 0.205
OD 0.498
Thickness 0.12
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4027-059

ID 0.123
OD 0.499
Thickness 0.059
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4028-010

ID 0.46
OD 0.562
Thickness 0.01
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4029-010

ID 0.377
OD 0.627
Thickness 0.01
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-403-036

ID 0.14
OD 0.408
Thickness 0.036
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4030-001

ID 0.376
OD 0.629
Thickness 0.001
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4035-024

ID 0.095
OD 0.182
Thickness 0.024
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4036-031

ID 0.127
OD 0.187
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4037-031

ID 0.139
OD 0.245
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4038-031

ID 0.134
OD 0.286
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4039-020

ID 0.191
OD 0.312
Thickness 0.02
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4040-046

ID 0.185
OD 0.373
Thickness 0.046
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4041-021

ID 0.21
OD 0.375
Thickness 0.021
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4042-018

ID 0.236
OD 0.42
Thickness 0.018
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4044-035

ID 0.253
OD 0.436
Thickness 0.035
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4045-040

ID 0.238
OD 0.437
Thickness 0.04
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4046-047

ID 0.317
OD 0.479
Thickness 0.047
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

Stainless Steel Flat Washer Frequently Asked Questions

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

What are stainless steel flat washers?
Stainless steel flat washers are manufactured from austenitic stainless steel, most commonly Type 301, Type 302, or Type 304. These alloys offer excellent corrosion resistance in most environments, good mechanical strength, and are non-magnetic in the annealed condition. Stainless steel washers are the most widely used corrosion-resistant metal washers across industrial, food service, marine, and architectural applications.

What is the difference between 301, 302, and 304 stainless steel washers?
Type 301, Type 302, and Type 304 are all austenitic stainless steels with similar corrosion resistance and mechanical properties. Type 301 offers higher strength and work-hardening characteristics, making it useful in spring and formed applications. Type 302 and Type 304 are nearly identical, with the primary difference being carbon content: 304 has a lower maximum carbon content (0.08% vs. 0.15% for 302), which provides slightly better weld corrosion resistance. For most washer applications, all three grades perform reliably.

When should I use stainless steel washers instead of zinc-plated steel?
Stainless steel provides inherent corrosion resistance that does not depend on a coating. Zinc-plated steel washers will corrode if the zinc coating is scratched, worn, or exposed to chlorides. For outdoor, marine, food service, pharmaceutical, or long-term corrosion resistance requirements, stainless steel is the better choice.

Can you make custom stainless steel flat washers?
Yes. Superior Washer manufactures custom stainless steel washers to your OD, ID, and thickness specifications. Contact us via the Quick Quote form or by phone.

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

Stainless steel is one of our most popular corrosion-resistant materials. Browse the full flat washers catalog to see everything we offer.