These large custom round spacers were manufactured domestically using 18-8 stainless steel material with plain finish – no passivation was required either for these specific parts.  The outside diameter was set at 1-1/2″ +/- .01″ and the inside diameter at 1/2″ +/- .01″.  Overall length measured 2″ with the same tolerance as the other dimensions.  Slight chamfer was added on both sides to smooth out the sharp edges.