... joint:Inside material: made of copper tube T1,the surface is silver-gilt Close-End Wire Connectors,Wire Joint,wire connector ... connections between wires. 2.Just strip off the wire and insert securely inside the connector, crimp by appropriate crimping tool. Shell ... certificated by ULInside material: made of copper tube T1,the surface is silver-giltTrail: nylon shell,long copper tube,easy to conduct ...