Description: 【Premium Material】: The bike chain guide is made of quality aluminum alloy material, lightweight, high strength, providing a better riding experience. 【Design】: Our chain guide is suitable for a wide range of bicycle types, and the chain/connecting post is adjustable in multiple places. Bike Chain Guide: 20.5cmx20cm/8.07inchx7.87inch, Conversion Seat: 6.8cmx7cm/2.68inchx2.76inch. 【Effective Chain Protection】: The bicycle chain guide can effectively prevent the chain from falling off and moving, without worrying about dropping the chain and extending the life of the chain, and smoother ride. 【Easy to Install】: The seat tube clamp chain guide is easy and convenient to install, adjustment with wrench, no need to disassemble the crank. 【Wide Application】: The bicycle chain protector is a useful tool for bicycle owners to improve their bicycles, It is simple and stylish, suitable for matching bicycles of various colors. Specification: Material: Aluminum Alloy Size Chart: Bike Chain Guide: 20.5cmx20cm/8.07inchx7.87inch Conversion Seat: 6.8cmx7cm/2.68inchx2.76inch Package Includes: 1 Bike Chain Guide 1 Conversion Seat Note: Please allow slightly errors 1-2cm differences due to manual measurement.