Unior 20 Tooth Cartridge BB Tool A High-Quality Tool Whether you're cleaning your bike, doing a full overhaul, or you're replacing an old bottom bracket, having the right tools makes the job much easier. The Unior 20 Tooth Cartridge BB Tool is designed to work with square taper, Shimano Octalink, ISIS, and other internal bottom brackets. It works with a 1/2" ratchet or an adjustable wrench to install and remove cartridges. Features Made of hardened tool steel so it should last a life time Designed for square taper, Shimano Octalink, and ISISWorks with 1/2" ratchets or adjustable wrenches | Unior | 20 Tooth Cartridge Bb Tool Black