The Ritchey WCS Zero Integrated Headsets are compatible with frames designed for the Campagnolo Hiddenset. The Cyclocross (CX) models have a pivoting housing stop for easier cable routing and lower friction. The CX models have a 15.3mm top cap height. This piece features a black alloy bearing cover, alloy crown race, stainless steel angular contact bearing packed with Ritchey grease. These fit Campagnolo-compatible head tube integrated style, fits 42mm ID head tubes and 45/45 degree angular contact bearings fit directly into head tube. Designed for 46mm OD head tube.