ITEM NAME:Aluminum Turbo Sound Whistle Exhaust Pipe Tailpipe BOV Blow-off Valve Simul E5U5 Aluminum Turbo Sound Whistle Exhaust Pipe Tailpipe BOV Blow-off Valve Simul E5U5 Specifications: Color: Black Material: Aluminum Size: XL Diameter: Approx. 3.3cm / 1.3in Length: Approx. 11.5cm / 4.5in Weight: 120g / 4.23oz Package includes: 1 * Turbo Sound Whistle; 1 * Small Spanner; 1 * Screw Installation: 1. Loosen the bolt on the Turbo Sound Whistle. 2. Insert the the Turbo Sound Whistle into the tailpipe. 3. Tighten the bolt so as not to fall off while driving. Notes: 1. Please make sure the tailpipe is big and long enough to contain the Turbo Sound Whistle. 2. Professional installation is always recommended, products damaged through self-installation will not be refunded. 3. Please check and re-tighten the bolt regularly." After installed this product, the pressure blowing out of your exhaust will make your vehicle sounds like a turbo vehicle with the turbo system or blow off valve. Made of high quality aluminum, light weight and durable. Easy to install on the car's tailpipe. Notes: 1. Please make sure the tailpipe is big and long enough to contain the Turbo Sound Whistle. 2. Professional installation is always recommended, products damaged through self-installation will not be refunded. 3. Please check and re-tighten the bolt regularly. even though it is water-resistant. Note:Light shooting and differnent displays may cause the color of the item in the picture a little different from the real thing.The measurement allowed error is  ±1-3 cm..Insert the the Turbo Sound Whistle into the tailpipe. Easy to install on the car's tailpipe. Loosen the bolt on the Turbo Sound Whistle. After installed this product, the pressure blowing out of your exhaust will make your vehicle sounds like a turbo vehicle with the turbo system or blow off valve.