The FSA BB30 Road Ceramic Bottom Bracket is 2 bearings that are directly pressed into the frame & seated against a cir-clips that are installed into machined grooves in the bottom bracket shell. To have a BB30 compatible shell on your frame the inner diameter needs to measure 42mm & have no threads on the inside. The ceramic bearings will give you a 4% increase in speed over standard bearings, so if your looking to upgrade your current BB30 this is what to go for. It comes with Wave spring, bearing covers, cir-clips & nylon adjustment washers. This BB will work with FSA BB30 Vision Trimax Carbon & K-Force Light BB30 cranks.