Well,this clamp is an accessory for bicycle seat post,which is made from full carbon fiber,it is high intensity and durable.31.8mm is suitable for 27.2mm seatpost.
It is an accessory that can help adjusting your seat post's height.Practical,tough,easy to handle. Suitable for majority of bicycle.
Material: Full Carbon Fiber
Type: Seatpost parts
Color: As pictures shown
Size: Diameter: 31.8mm(1.25in)