Milwaukee Twins Chrome Straight Petcock With External Threads Milwaukee Twins Petcock has been engineered to eliminate all internal O-rings while the inner core was designed to insures against gas leakage while providing maximum flow. Features 1/4 vertical outlet that accepts 1/4 fuel line and on/off/ reserve functions. Features: No internal O-rings Inner core design insures against gas leakage while providing maximum flow Filter screen On/off/ reserve functions Chrome body