Isolate pneumatic energy without the expense and inconvenience of installing in-line lockout valves|Device is applied to the male fitting, isolating equipment from all compressed air sources|Accommodates the majority of 1/4 in, 3/8 in and 1/2 in male fittings|Hole in center of device allows for permanent storage on an air hose and a loop on the side can be used to hang the hose and lockout device|Accepts padlock with up to 1/4 in shackle