Nylon breaker A mounting bracket 4-gang Accept Cole Hersee brand 30056 series and 30137 series circuit breakers. Durable, lightweight molded nylon. Breakers mount securely using stud and hex nut. Mounting holes 0.280' x 0.440" (7.1 x 11.2mm). slots are 0.910 (23.1mm) on centers and 0.210" wide (5.3mm). 5.69" long (114.5mm). Mounting holes 4.89" (124.2mm) on centers.