Constructed from precision-machined 4140 steel, the BBT-118 is a heavy duty tool for the removal and installation of select bicycle components with an eight-notch tool fitting. The BBT-118 is designed to be compatible with any bottom bracket with the corresponding tool fitting, with an extra-deep body to accommodate extra-wide spindles and low-profile walls at the point of engagement for recessed lockrings. The BBT-118 has three methods of tool engagement--a 3/8" drive fitting, a 1" hex fitting, and 36 mm wrench flats--allowing you to take on even the most seized components. For added stability, the BBT-118 features integrated threads for use with the Park Tool BBT-RS Bottom Bracket Tool Retaining System or GPS-1 Guide Pins (each sold separately).Installs and removes the following components with eight-notch tool fittings:- Shimano(R) Octalink(R) drive-side bottom bracket cups with external notches- ISIS Drive bottom bracket cups including Truvativ(R) and Bontrager(R)- Front chainring lockring for Bosch(R) Gen 3, Gen 4, and Gen 5 e-bike systems- Front chainring lockring for Specialized(R) Levo Brose e-bike systemsTool specifications:- 3/8" drive fitting- 1" and 36 mm wrench flats- 8 notches with a nominal inside diameter of 37.6 mm and outside diameter of 42.7 mm- Internal clearance: 31.14 mm (1.226") depth (from tool face) x 22.48 mm (0.885") diameter- Not rated for use with impact drivers