EXTSW 3/8” ID x 1 1/2” OD x 3/16” Thick 316 Stainless Washer
Actual dimensions .383" ID x .1.490" OD x .188" Thick
(+/- .003" on all dimensions) 
.030 inch Radius OD / slightly countersunk ID (no sharp edges)
 Made in USA. 316 Stainless has the ULTIMATE corrosion resistance.