Designed for use on circuits where contact with water or another ground is possible while using an electrical device. One inch module, 10,000 AIR, 5 milli-amp (.005 amp) ground fault trip level. Push to test button. May be used when marked to accept with American Switch, Arrow Hart, Bryant, General Switch, GTE, Sylvania, most ITE, Murray, Westinghouse Type BR, Challenger. 60 Hz. UL Listed.