Its a retainer of somekind and might explain why they were $4+ each instead of the $2 or so I was expecting. Everything I've used to look up valve spring retainers for a 3.1l chevy comes up with those things aswell so I am getting a little frustrated. I can find the right ones under Gm goodwrench performance parts but I can't find prices. Not even sure I can walk into a dealer with one of those parts #s and order anything.