You are purchasing 12 NOS (New Old Stock) exhaust valve seats for the Jaguar V12 H.E. XJ12 XJS.
These are .003 oversize.
Each seat is marked M.W.W. Spec 1.504 (photo 2 and 3).
New from a vintage British inventory, part number EAC3641 .003. {B W}
Photos are the actual part.
Please see our auctions and ebay store for more NOS new and one of a kind parts.
Thanks.