Shimano SL-LS10 is a shifting lever compatible with Shimano RS rear derailleurs. It is designed to provide smooth, precise gear changes with minimal effort. The lever features a free-play mechanism that allows for some flexibility of movement, ensuring that the derailleur can adjust itself to the correct position based on the chain's tension. This results in reduced chain noise and faster, surer gear shifts. The SL-LS10 is designed for use with rear freewheel sprockets having 13T to 34T, and the combined total of teeth number difference between front gear and rear gear should be 34T or less.