This is a seat tube clamp specially designed for fixed-gear bicycles. It is suitable for 25.4 seat tubes with a specification of 28.6. It features a screw-type design and is made of aluminum alloy, which is sturdy and durable. It can provide a reliable seat tube fixing solution for your bicycle. The aluminum alloy material not only ensures the strength of the seat tube clamp but also has the characteristic of being lightweight, so it won't add too much burden to the bicycle and makes cycling easier. The screw-type design makes installation and disassembly very convenient. Even if you are not a professional bicycle maintenance person, you can easily complete the operation. This seat tube clamp is compatible with 25.4 seat tubes and the 28.6 specification, which can well meet the usage needs of most fixed-gear bicycles and provide stable support for your cycling. Whether you are cycling daily or participating in some bicycle races, it can handle the task.