Description: Please check your bike frame seat tube outside diameter. Measure the inside diameter of your old clamp. Or measure the outside diameter of your seat tube (on your bike frame). Then make a right choice. Bicycle Seatpost reducer matches well with most bicycles, such as MTB ,BMX ,mountain bike, road bike,and more, you can easily adjust the diameter of the bicycle seat post, eliminating the trouble of repurchasing the bike seatpost. 1-Open the clamp. 2-Put the seat post and shim adapter in. 3-Adjust the post height. 4-Lock the clamp Just purchase this product, you can easily adjust the diameter of the bicycle seat rod, eliminating the trouble of repurchasing the seat rod. Material: aluminum alloy Size: 22.2 25.4 27.2 30.9 31.6 to 28.6 30 30.4 30.8 30.9 31.6 33.9 Total length: Approx. 100mm/3.9inch Package includes: 1x Bike Seat Post Shim
