●【High Quality Material】The chain tensioner is made of high-quality aluminum alloy material, fully precision CNC machined, sturdy and durable, with strong corrosion resistance and water resistance, and can withstand harsh climatic conditions. ●【Automatic Mechanical Tensioning Function】The automatic mechanical tensioning function can effectively compensate for the elongation of the chain, which is very suitable for heavy load occasions. Using a chain tensioner can make the chain run more smoothly and reduce the noise and wear of the chain and sprocket. ●【Adjustable Design】Adjustable chain tensioner design, the floating pulley and spring adjustment can achieve perfect chain tension. ●【Easy to Use】This bike chain tensioner is lightweight and easy to install. ●【Wide Application】This single speed converter is very suitable for mountain terrain bikes and single-speed folding bikes, can be used with various guide wheels.