Super-smooth steering, quality materials, cutting-edge design and serious durability are all hallmarks of Cane Creek's 40-Series headsets. - Technical Description: IS42/28.6/H9/K|IS52/40/H1 - Top Type: IS - Integrated - Top Head Tube Inside Dia.: 42.00mm - Stem Clamp Dia.: 28.6mm - Top Stack Height: 9mm (Short), 15mm (Tall) - Top Bearing Type: Black Oxide, Sealed - Bottom Type: IS - Integrated - Bottom Head Tube Inside Dia.: 52.1mm - Crown Race Seat Dia.: 39.79mm - Crown Race Type: Steel, Face-Sealed - Bottom Stack Height: 1mm - Bottom Bearing Type: Black Oxide, Sealed - Material: 6061 aluminum - Weight: 84g