Gardner Bender Wire Connectors are engineered to exceed the expectations of professional electricians. Perfect for commercial or residential applications GB Wire Connectors offer world-class quality, performance and application versatility. Hi-Temp twist-on wire connectors are specifically designed to withstand hi temperature and other tough environments. Manufactured with high-temperature-rated plastic that is grooved for comfortable twisting. Designed for copper to copper wire connections from 18 to 10 AWG.