US STAINLESS Stainless Steel 316 Round Ring Welded 3/8" x 1 5/8" (10mm x 40mm ID) Marine Grade

Weld is a bit sloppy and the ring is warped (it does not lie flat). Also the internal diameter is a little over 41mm, so it's not even close to being in spec. For the price, one should be able expect much better quality.