Comparison : Item # 400078-001, Complete Kit and Assembly
Item # 400077-701, 2 Inch (in) 4D-MT Vapor Release Cover Assembly
Item # 004853-008, 5/8 - 18 Inch (in) Hex Head Retainer Screw
Item # 100024-003, Compression Spring
Item # 100138-006, 1/16 Inch (in) Sect BUNA N O-Ring