U34365.018.0050-A Rivet Washer, Washer Shape Square, Steel, Fastener Finish Plain, Washer Inside Dia. 3/16 in, Washer Outside Dia. 1/2 in, Washer Thickness 0.056 in, Standard, Thickness Tolerance 0.052 in to 0.060 in, For Use With Rivets, Package Quantity 500