Our 1997-2004 Coolant System Air Bleed Pipe Assembly is manufactured by General Motors for a direct fit replacement for any 2001-2004 Corvette. This pipe assembly is also required when updating any 1997-2000 LS1 engines with a later 2001-2004 LS6 intake manifold. This Cooling System Air Bleed Pipe Assembly includes the necessary O Ring for proper installation.