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 4401–4450 of 4,985 products

SKU ID OD Thickness Material ID TOL OD TOL Quantity

300-489-046

ID 0.151
OD 0.373
Thickness 0.046
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4890-002

ID 0.379
OD 0.748
Thickness 0.002
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4891-003

ID 0.379
OD 0.748
Thickness 0.003
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4894-057

ID 0.384
OD 0.499
Thickness 0.057
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4896-117

ID 0.391
OD 1.0
Thickness 0.117
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4897-051

ID 0.406
OD 1.25
Thickness 0.051
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4898-059

ID 0.408
OD 0.875
Thickness 0.059
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4899-062

ID 0.421
OD 0.811
Thickness 0.062
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-490-025

ID 0.151
OD 0.373
Thickness 0.025
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4901-118

ID 0.438
OD 1.0
Thickness 0.118
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4902-029

ID 0.44
OD 0.629
Thickness 0.029
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4903-058

ID 0.471
OD 0.746
Thickness 0.058
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4904-057

ID 0.501
OD 1.123
Thickness 0.057
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4905-012

ID 0.513
OD 0.748
Thickness 0.012
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4907-088

ID 0.535
OD 1.062
Thickness 0.088
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4909-103

ID 0.563
OD 1.374
Thickness 0.103
Material Stainless Steel
ID TOL +-.010
OD TOL +-.010
Quantity

300-4912-058

ID 0.627
OD 0.996
Thickness 0.058
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4913-012

ID 0.628
OD 0.765
Thickness 0.012
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4914-039

ID 0.643
OD 0.996
Thickness 0.039
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-492-010

ID 0.151
OD 0.59
Thickness 0.01
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-4920-048

ID 1.002
OD 1.248
Thickness 0.048
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-493-032

ID 0.151
OD 0.622
Thickness 0.032
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-494-015

ID 0.152
OD 0.243
Thickness 0.015
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-495-029

ID 0.152
OD 0.252
Thickness 0.029
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-496-031

ID 0.152
OD 0.273
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-497-005

ID 0.152
OD 0.306
Thickness 0.005
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-498-040

ID 0.152
OD 0.317
Thickness 0.04
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-499-041

ID 0.152
OD 0.406
Thickness 0.041
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-50-005

ID 0.04
OD 0.079
Thickness 0.005
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-500-005

ID 0.152
OD 0.436
Thickness 0.005
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-501-020

ID 0.152
OD 0.476
Thickness 0.02
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-502-030

ID 0.152
OD 0.5
Thickness 0.03
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-503-032

ID 0.152
OD 0.559
Thickness 0.032
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-504-035

ID 0.152
OD 0.658
Thickness 0.035
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-506-024

ID 0.152
OD 1.001
Thickness 0.024
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-508-024

ID 0.154
OD 0.327
Thickness 0.024
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-509-037

ID 0.154
OD 0.748
Thickness 0.037
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-51-005

ID 0.04
OD 0.12
Thickness 0.005
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-510-037

ID 0.156
OD 0.239
Thickness 0.037
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-511-005

ID 0.156
OD 0.246
Thickness 0.005
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-512-005

ID 0.156
OD 0.25
Thickness 0.005
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-512-010

ID 0.156
OD 0.25
Thickness 0.01
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-512-015

ID 0.156
OD 0.25
Thickness 0.015
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-512-020

ID 0.156
OD 0.25
Thickness 0.02
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-512-025

ID 0.156
OD 0.25
Thickness 0.025
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-512-031

ID 0.156
OD 0.25
Thickness 0.031
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-512-040

ID 0.156
OD 0.25
Thickness 0.04
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-513-029

ID 0.156
OD 0.252
Thickness 0.029
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-514-047

ID 0.156
OD 0.255
Thickness 0.047
Material Stainless Steel
ID TOL +-.005
OD TOL +-.005
Quantity

300-515-030

ID 0.156
OD 0.261
Thickness 0.03
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.