The Master Lock No. 506 Grip Tight™ Circuit Breaker Lockout combo pack includes one 491B and one 493 Grip Tight™ circuit breaker lockout. The innovative and patented Grip Tight design effectively locks out circuit breakers with a simple operation and the durable construction with powder coated steel and reinforced polymer stands up to harsh environments. Devices are compact and accept all American Lock® and Master Lock® safety padlock shackles and most lockout hasps.