Size: 27.2mm to 30.4mm. Inner diameter: 27.2mm/1.07', Outer diameter: 30.4mm/1.19', Length: 60mm/2.36' Material: Made of aluminum alloy, anti-slip, anti-rust, durable in using. Color: Black Installation: Easy to install and remove, no drilling or cutting required, no tools are needed, just a few seconds to install directly to the bicycle. Application: This product is suit for most bicycles such as MTB bike, mountain bike, road bike, etc. Please check the outer diameter of your bicycle seat tube before placing the order. Measure the inner diameter of the old clamp or the outside diameter of the seat tube. Then make the right choice.