Home » headsets » Integrated Headsets » p507a INTEGRATED HEADSETS P507A Angle-Limited ZS42/28.6 | IS52/40 Patent No: M579129 Alloy, Sealed Bearings 1-1/8″ to 1.5″ Tapered Head Tube & Steerer Top Nut: 1-1/8″ Cup/Bearing O.D.: 42/52 Crown Cone: 39.8 Height: 15.7 Weight: 139g Technical Diagram