These lockable vapor caps act like dust covers, but won’t activate the Air Interlock Valve when used on vapor check valves and adapters. Iron-copper infiltrated cams create a solid push-down-and-pull-up movement for quick, easy removal and replacement; steel latches hold the caps secure. Orange in color to indicate vapor recovery, the caps can be used with any 4" male cam and groove. Caps also available with finger ring and chains.