Brady Red LOTO-39 Nylon Polypropylene and Glass Filled Impact-Modified Nylon Oversized Breaker Lockut features new blade design with improved grip and offers chemical resistance as well as durability. Breaker Lockut can be applied easily with thumbscrew mechanism and does not require a screwdriver. It is the ideal device for 480/600V switches up to 2 1/4" wide and 7/8" thick. Glass-filled nylon has a service temperature of -20 to 120 deg C and polypropylene features a service temperature of -20 to 80 deg C.