The inner bearing tool TO-S91 from XLC makes inserting and removing inner bearings on your bicycle a more straightforward task. You will not need to spend money on expensive mechanics and visits to your local bike shop, as you can now perform bearing removal and insertion from the comfort of your own home. The TO-S91 is designed to be used with an external inner bearing with 12 grooves. These types of bearings are found on most types of bikes, including mountain, race, city, road and trekking. When attached to the correct puller or handle, this tool from XLC can make bearing insertion and removal easy and means you will not damage your frame or bearings during the process like you might if you used home substitutions such as hammers.