Shimano SL-M951 Rapidfire Remote shifters allow cyclists to change gears quickly and easily with just a flick of the thumb, without having to remove their hands from the handlebars. Compatible with Shimano XTR series Rapidfire SL-ST-M951 / SL-M951 levers, these shifters can be mounted to many aftermarket extensions that have a straight section at the end, making them a versatile addition to any mountain bike setup.