Color-coded connectors for copper-to-copper use with tight, square-wire spring for quick and secure connections. Tough thermoplastic shell shields against environmental extremes and resists chemical action from hydrocarbons, diluted acid, or alkaline solutions. Flame-retardant properties resist heat distortion up to 105 degrees Celsius. High-dielectric shell features deep skirt design to prevent exposure of bare wire. Contains: 3 gray (#22-#16 American Wire Gauge), 4 blue (#22-#16 AWG), 6 orange (#22-#14 AWG), 6 yellow (#18-#10 AWG), 6 red (#18-#10 AWG).