The CeramicSpeed Coated Gravel Bottom Bracket ensures smooth and silent function of your crankset along with easy connection to the frame. The bearings are coated, improving efficiency and lifespan. The bottom bracket also features dust covers to keep debris away, maintaining smooth function. This version is designed for Threaded shelled frames like Specialized. It pairs with 30mm spindle cranksets. The CeramicSpeed Gravel Coated Bottom Bracket is the best way to maximize performance and pedaling on your gravel adventures.