Features: Lightweight and Durable. Make your car sound like a turbo vehicle with the turbo system or blow off valve. Easy to install，No welding or drilling needed.Wrench and black screw is used to fix the item. Diameter:2.5CM Lenght:10.5cm Color:Silver Installation: 1. Loosen the screw on the Turbo Sound Whistle 2. Place the Turbo Sound Whistle body inside the exhaust muffler with the larger opening facing the inside of the muffler 3. Screw the screws on the Turbo Sound Whistle to tighten the item so it doesn't fall off while driving 4. Professional installation is always recommended， products damaged through self-installation will not be refunded. Package Included:1 X Turbo Sound Simulator Whistle