The Pack Tool Wrench and Inserts Kit Ultralight BB Wrench and 1-Inch Hex Inserts is designed to provide a bike tool solution that is compact and lightweight enough to carry with you on the road but still be durable enough for everyday use. The aluminum wrench has magnets that hold the nickel plated steel inserts in place. The wrench has splines for bottom brackets and centerlock rotors and the four included inserts cover most common bike applications. Pack Tool Wrench and Inserts Kit Ultralight BB Wrench Features Pack Wrench - ultralight 1 hex and bottom bracket wrench Ultralight Cinch and ISIS Spline Wrench Insert - older ISIS bottom brackets or the Race Face Cinch direct mount chainring system Ultralight Cassette Lock Ring Wrench Insert - cassette lockrings and some centerlock rotor lockrings Ultralight 8mm Hex Wrench Insert - pedal removal and other 8mm hex applications Ultralight 16mm Hex Wrench Insert - Race Face Cinch aluminum spindle bolts, frame pivots, and other 16mm hex applications All inserts are made in the USA and CNC machined from hardened steel with electroless nickel plating.