- Quickly and accurately indicates the bicycle chain wear. - Fits 5 to 13 speed chains. (including SRAM® T-Type, SRAM® Flattop™, and Shimano® XTR® 12 speed chains) - 5-to-10-speed chains: replace chain at or just before 0.75%. - 11-to-13-speed chains: replace chain at or just before 0.5%.