CYSKY Seatpost Adapter Shim Bicycle Seat Post Tube Adapter Seatpost Reducing Sleeve Shim for Mountain Bike Road Bike MTB BMX Fixie Gear 25 4mm to 27 2mm

Material: Aluminum alloy Length: 60mm Size: Convert a 25.4 seat post to fit a 27.2 seat tube. Convert a 27.2 seat post to fit a 30.8 seat tube. Convert a 27.2 seat post to fit a 31.6 seat tube. Convert a 27.2 seat post to fit a 33.9 seat tube. Convert a 33.9 seat post to fit a 34.9 seat tube. Suit for MTB bike, mountain bike, road bike etc. Package Includes: 1 Piece of Seat Post Adapter Note: 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.