Home » headsets » Tapered Headsets » p563a TAPERED HEADSETS P563A IS42/28.6-26tpi | IS52/40 Alloy Sealed Bearings 1-1/8″ to 1.5″ Tapered Head Tube & Steerer Top Nut: 25.4 Bearing O.D.: 41.8/51.8 Crown Cone: 39.8 Height: 17.5 Technical Diagram