1Made of full CNC precision machining aluminum alloy, anti-slip. 2Easy to install and remove, convenient for you to use. 3With this seat post tube adapter, you can change the bicycle seat tube to the size you want. 4Suitable for MTB bike, mountain bike, road bike, etc. 5Please check the outer diameter of your bicycle seat tube. Measure the inner diameter of the old clamp. Or measure the outside diameter of the seat tube. Then make the right choice.