Quick view #4 Flat Washers, AISI 304 Stainless Steel (18-8) Type 304 stainless steel is defined as a Chromium-Nickel austenitic alloy.Stainless steel significantly improves resistance to tarnishing or corrosion.The nominal diameter is the bolt size to use for this flat washer.Diameter (Nominal): #4Inside... $408.94 Select Quantity Compare