Lockout devices control energy sources and ensure machine and equipment remain inoperable to prevent unexpected start-up or release of stored energy in accordance with OSHA 29 CFR 1910.147 requirements. The STOPOUT low profile circuit breaker lockout fastens tightly onto circuit breaker for a secure, solid lockout. Easily install with just a standard flathead screwdriver (Over-tightening the setscrew may damage the circuit breaker.) This unique design allows for easy lockout application and removal. Fits most 120/240 circuit breaker sizes and accommodates up to 9/32 in diameter padlock shackles (sold separately). The slim, low-profile design stores easily. Red octagon shape reinforces lockout status and conveys STOP.