Insulated Wire Connectors Multi Splice Connector, 5 Pcs,4-14 Wire Range, Slotted Heavy Duty Insulation: wire connectors terminals are insulated with strong high dielectric rubber and vinyl coating for long term use, suitable for copper or aluminum conductors, and prevents oxide formation Simple to Use: dual entry insulated in line cable connectors can be easily reinserted for inspection and troubleshooting, quick and convenient to use Pre Filled: 2 wire cable connectors are pre filled with oxide inhibitors to withstand temperatures ranging from -49 to 194 degrees Fahrenheit; 600 Volt cable conductors are aluminum CU9AL dual rated for use with copper and aluminum wire for added safety Size and Specifications: the insulated wire connector kit has an external size of about 1.16 x 1.38 x 1.26 inches and accepts 4-14 wire range designs, slotted; Each connector is marked with the maximum length of the wire, so you don't have to worry about the wire connector fit, and you can fit one wire into each terminal, making it a must have in electrical tool box Distinctive Design: wide range of electrical connector: 750Kcmil-14, 600V, 90C, low temperature rating of -45C; The removable connector is suitable for daily use