Brand New Pair of 3156 3157 3057 3357 3457 4157 Light Bulbs Extension Wiring Harness with pre-wired Socket Connectors Pre-Wired Socket for Easy Plug and Play They are easy DIY installation, just simply connect the wires of the socket connector to any 12V power source and insert a correct size light bulb. All connectors has + AND - wires. If the bulb doesnt light up, please rotate the bulb 180 degree and reinsert again. Please make sure the power is OFF during installation. Compatible Bulb Sockets: 3156, 3157, 3057, 3357, 3457, 4157 etc Package Contents: One Pair (2 pcs ) 3157 wire socket cable