Master Lock® Circuit Breaker Lockout, 1-Pole Clamp-On, series: Grip Tight™, For Use With: Master Lock®, American Lock® Safety Padlocks and Lockout Hasp, 120/277 VAC Circuit Breaker, 1 Padlocks Maximum, 9/32 in Padlock Shackle Maximum Diameter, Red, Steel, 1-1/4 in Height, 3-1/2 in Width, 3-1/2 in Depth. Master Lock® 491B Grip Tight™ 1-Pole Clamp-On Circuit Breaker Lockout, 120/277 Vac, Red, Steel, 9/32 in Max dia Padlock Shackle