The industry's standard twist-on connector with quality performance and durability. GB specifies this connector for a wire range of 22 16 AWG and recommends a wire combination of minimum (3) 22 wire and maximum (3) 16. It is blue in color for easy color code identification. Recommended for copper to copper connections only. Made from tough, thermoplastic shells which guard against hydrocarbons, diluted acid or alkaline solutions. Color-coded for easy size selectionThree #22 minimum wire and three #16 maximum wireMakes quick, secure connections for positive continuity, tightens without ratcheting, yet removable for re-useTough, thermoplastic shell shields against environmental extremes, smooth surface eliminates porosity and crackingResists chemical action from hydrocarbons, dilute acid or alkaline solutionsFlame retardant properties resists heat distortion up to 105 degrees C, 221 degrees FHigh-dielectric shell features deep skirt design to prevent exposure of bare wireCopper to copper connections onlySuperior flash-over protectionVersatile size selection covers building wire combinations from #22 to #16 AWG