Easily adjustable speed setting for precise chain tension, enhancing your cycling efficiency. Prevents chain drop when folding the chain hook of bicycles. It is installed on the rear derailleur guide wheel frame for secure operation. Designed specifically for folding bikes, this tensioner ensures a fit and reliable function on folding frames. Features a rear derailleur mount and guide wheel for stable, drop chain management. Key benefits Improves pedaling efficiency with a finely tunable tension setting. Reduces risk of chain drop during folding or riding, giving peace of mind. Tailored for folding bikes to ensure a snug fit and dependable performance. Built around a rear derailleur mount and guide wheel to keep the chain under control in all conditions. Compatibility and installation Designed for folding bikes that use a rear derailleur guide wheel frame. Mounts on the rear derailleur frame to provide stable chain management. Performance attributes Reliable, drop chain control on folding bicycle setups. Simple adjustment to maintain chain tension across riding conditions. Use scenarios City commuting with a folding bike: maintain consistent chain tension for smooth, efficient riding. Folding and unfolding in transit (train, bus, or car): prevent chain drops during folding operations. Drivetrain upgrades or maintenance on a folding bike: or upgrade to improve chain tension and stability.