Doing some home repairs, one of these is a must, might only get used a few times but the convenience of having t to not having it, 3 options on hand IceToolz 39mm 16 Tooth Bottom Bracket Installation ToolFor Shimano XTR and Shimano Dura-Ace compatible bottom brackets. Features 16 Tooth 39mm Diameter Use with 1/2" driver Dimensions measure 4.6cm x 4.6cm x 2.8cm Weighs 119g Constructed from Cr-Mo steel IceToolz 41mm 16 Tooth Bottom Bracket Installation ToolFor Shimano Ultegra 6800 (11-speed) and Shimano MT-800 compatible bottom brackets. Features 16 Tooth 41mm Diameter Use with 1/2" driver Dimensions measure 5.0cm x 5.0cm x 2.8cm Weighs 153g Constructed from Cr-Mo steel IceToolz 44mm 16 Tooth Bottom Bracket Installation ToolFor Campagnolo Ultra-torque, Shimano Hollowtech II, and Truvativ Howitzer compatible bottom brackets. Features 16 Tooth 44mm Diameter Use with 1/2" driver Dimensions measure 5.5cm x 5.5cm x 3.4cm Weighs 219g Constructed from Cr-Mo steel