Bussmann Fuses 20A FRN-R Cartridge Fuse, 2-Pack is a heavy-duty Fusetron dual element, time delay cartridge fuse designed specifically for motor protection. It effectively helps prevent motor burnout caused by overloads or single phasing. The time delay feature allows the initial startup surge typical of motors to pass safely, while opening the circuit before burnout occurs during longer, more dangerous overloads. This fuse is UL listed as Class R with a 200,000 AIR (amp interrupting rating) and operates at 250V. Fuses rated from 1/10A to 60A have ferrule ends, while those from 70A to 200A feature knife-blade ends, ensuring reliable performance for a variety of applications. Model Number: 20A FRN-R