This is a versatile ORIGIN8 MULTI-FIT adjustable bicycle seatpost shim designed to fit posts ranging from 25.4mm to 26.4mm-28.0mm. Made of high-quality aluminum material, it is lightweight and durable, ensuring a safe and comfortable ride. The shim comes with a compatible shim to help with installation. Suitable for universal bikes, this seatpost shim is a must-have for any cyclist looking to upgrade their bike components.