Pedro's External Bottom Bracket Cup Socket Tool Description: Pedro's External Bottom Bracket Cup Socket Tools stand as a reliable option for home-repair and shop-repair users looking to address a wide array of bottom brackets and other 44mm diameter, 16-notch lockring style fittings found on modern mountain and road bikes. Features: Fits 16-notch external bottom brackets with 44mm outer diameter Updated tool design fits 16-notch x 44mm disc brake lockrings Compatible Shimano TL-FC24 and TL-FC25 bottom bracket adapters Hex end works with Pedro's Pro Socket Handle, 24mm socket or wrench, or in a bench vise Design features a square 3/8" drive permitting use with torque-wrenches