Yea, well it says #460483 on the packet. It's a genuine GM part for '81-'92 V8, but it fit just fine on my '80. There pretty high quality seals, they have 2 metal rings to keep em in place. I got them from Chevparts in Yennora- $25 for 8. If your looking for umbrella seals, take a valve spring with you, the standard ones they sell everwhere were too big for mine.
So far so good, after 24h of standing the vette started clean, and eaiser too.
Adam