All of our bottom brackets are a universal fit requiring a Fit Kit specific to the model of crankset to be used. Our Fit Kits are made to account for crank manufacturers' machining tolerances and ensure they mate perfectly with our precision bearings, extending product life and reducing the potential for noise. They consist of two spindle sleeves and a varying amount of spacers and adapters. This page has individual spindle sleeves in case one has been damaged or lost. These are not complete Fit Kits. Spindle sleeves are sold individually Two are needed for a bottom bracket, however we would recommend purchasing a new Fit Kit if you need both as it includes new spindle spacers H, I, J, K, and L are all for 24mm cranksets L is the standard length offered in Fit Kit #4 and #6 These only work for our bottom brackets labeled 24 (ThreadFit 24, T47 24i/24x, PF24) DUB and 30mm are only for our bottom brackets labeled 30 (ThreadFit 30, T47 30i/30x, PF30)