These Shimano Revo twist shifters feature as original equipment on a number of bikes and would be an ideal replacement for worn of broken shifters. The right hand shifter is a 8 speed indexed unit fully compatible with shimano rear gear systems, with an optical gear display, to let you know which gear you are using. The left shifter offers features 3 position indexing and is compatible with Shimano front gears .This kit also includes inner gear cables.