These are the double sided, stainless steel swivels everyone (ok.. mostly glassblowers) have been talking about! These swivels are made in the USA in Rochester, MN. 304 Stainless will not rust under normal use. Don't put them in bleach, strong acid, or, we've been told, blood. (304 is a slightly magnetic stainless, but don't expect to be able to hold your swivel up with a magnet) This also means the swivel is lightweight.