Make quick, secure connections for positive continuity. Tough, thermoplastic shell shields against environmental extremes. The high dielectric shell features a deep skirt design to prevent exposure of bare wire while providing superior flash-over protection. Splices copper to copper. These connectors comply with Federal specification W-5-610d and are UL (Underwriter's Laboratories) 486C listed and CSA (Canadian Standards Association) certified. 300V/600V.