This diffuser comes with a real working LED 3rd brake light that will work with your brake lights. A wiring harness and install guide will be included with every diffuser. The Kholen style diffusers are made using our same genuine 2x2 carbon fiber fabric as our other M3/M4 parts. Each piece is clear coated for that brilliant shine and to help protect it from harsh road conditions. Each piece is then quality checked prior to shipping worldwide so rest assured when purchasing your diffuser that you will receive a top quality product.