These Billet lifters are manufactured specially for the use with the Billet WEBCAM cam shafts. Due to their special hardness you can’t use any other kind of lifters then the Billet lifters. So as from now you MUST use these lifters for each cam shaft from WEBCAM in order to avoid eventual guarantee cases. If these lifters have not been used, there can NEVER be any question of guarantee. Sold per set for 1 engine.