Versatile conversion This innovative chain adjuster turns multi-speed bikes into single speed wheels, providing a simplified and efficient riding experience. Its adaptability makes it a must have for cyclists looking to streamline their bike setup. Spring loaded design With a spring loaded mechanism, this chain guide effortlessly offers different gear sizes to ensure a secure fit. It effectively prevents the chain from spinning the crank and provides a smooth and reliable ride. Perfect chain tension Replace optimal chain tension with this adjuster, which reduces pedaling effort and improves overall performance. Its precision technology ensures a seamless and efficient cycling experience and makes every ride more enjoyable. Compatibility for rattling bike This chain guide is specially designed for folding bicycles with 11T or 13-t retaining ropes and fits perfectly with compact and portable bicycles. Its compatibility ensures firm adjustment and reliable performance for folding bike enthusiasts. Use scenarios - Urban commuting with a folding bike: convert to single speed to simplify maintenance and provide direct power transfer on flat or mildly rolling routes. - Travel with a compact folding bike: install before a trip to secure chain tension during transit and reconfigure quickly upon arrival for new routes. - Mixed terrain or rough pavement: use the chain adjuster to maintain secure chain alignment and stable performance, reducing the risk of chain drop on variable surfaces.