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 4101–4150 of 4,985 products

SKU ID OD Thickness Material ID TOL OD TOL Quantity

300-4286-033

ID 0.33
OD 0.874
Thickness 0.033
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4287-117

ID 0.409
OD 1.123
Thickness 0.117
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4288-059

ID 0.398
OD 1.248
Thickness 0.059
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4289-117

ID 0.565
OD 1.997
Thickness 0.117
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-429-031

ID 0.143
OD 0.687
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4291-020

ID 2.001
OD 2.499
Thickness 0.02
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4292-059

ID 0.134
OD 0.358
Thickness 0.059
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4293-060

ID 0.255
OD 0.369
Thickness 0.06
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4294-020

ID 0.201
OD 0.38
Thickness 0.02
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4295-063

ID 0.213
OD 0.482
Thickness 0.063
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4296-057

ID 0.206
OD 0.5
Thickness 0.057
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4299-063

ID 0.534
OD 0.999
Thickness 0.063
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4300-049

ID 0.284
OD 1.0
Thickness 0.049
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4301-078

ID 0.263
OD 1.5
Thickness 0.078
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4303-011

ID 0.13
OD 0.25
Thickness 0.011
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4304-030

ID 0.188
OD 0.253
Thickness 0.03
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4306-005

ID 0.263
OD 2.624
Thickness 0.005
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4308-032

ID 0.177
OD 0.375
Thickness 0.032
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4309-034

ID 0.284
OD 0.61
Thickness 0.034
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-431-032

ID 0.144
OD 0.217
Thickness 0.032
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4310-005

ID 0.407
OD 0.625
Thickness 0.005
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4315-032

ID 0.18
OD 0.5
Thickness 0.032
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4316-002

ID 0.377
OD 0.56
Thickness 0.002
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4318-102

ID 0.422
OD 1.0
Thickness 0.102
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4320-025

ID 0.092
OD 0.186
Thickness 0.025
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4322-059

ID 0.204
OD 0.498
Thickness 0.059
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4323-058

ID 0.386
OD 0.565
Thickness 0.058
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4324-078

ID 0.221
OD 0.625
Thickness 0.078
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4325-058

ID 0.392
OD 0.625
Thickness 0.058
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4327-020

ID 0.512
OD 0.749
Thickness 0.02
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4328-015

ID 0.781
OD 0.86
Thickness 0.015
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4329-125

ID 0.287
OD 1.0
Thickness 0.125
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-433-040

ID 0.144
OD 0.356
Thickness 0.04
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4330-020

ID 0.389
OD 1.019
Thickness 0.02
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4331-059

ID 0.781
OD 1.117
Thickness 0.059
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4332-005

ID 0.516
OD 1.12
Thickness 0.005
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4333-032

ID 0.122
OD 0.23
Thickness 0.032
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4334-016

ID 0.189
OD 0.249
Thickness 0.016
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4335-033

ID 0.135
OD 0.312
Thickness 0.033
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4336-047

ID 0.19
OD 0.436
Thickness 0.047
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4337-034

ID 0.258
OD 0.438
Thickness 0.034
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-434-050

ID 0.144
OD 0.383
Thickness 0.05
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4340-010

ID 0.378
OD 0.5
Thickness 0.01
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4341-050

ID 0.255
OD 0.512
Thickness 0.05
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4344-092

ID 0.409
OD 0.749
Thickness 0.092
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4345-059

ID 0.383
OD 0.75
Thickness 0.059
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4346-016

ID 0.457
OD 0.75
Thickness 0.016
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4347-060

ID 0.333
OD 0.752
Thickness 0.06
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-435-031

ID 0.144
OD 0.423
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4350-090

ID 0.535
OD 0.873
Thickness 0.09
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.