Valve Covers Chevrolet Big Block V8 396-454-502 Motor with 1 hole 1-1/4" for Breather or Pcv. 4" Tall Height will suit most Roller Rockers. Sold as a pair. Black Finned Aluminium Baffled. Grommet for Pcv is Part No 41900 and for Oil Cap our Part No 41901. Most Oil Caps with 1" Neck will fit such as our Part No's 66-012 and 66-013 Dome Style or 66-001, 66-002, 66-003, 66-044 Pleated Filter Style . Use Reusable Valve Cover Gasket MAG454G.