FSA Orbit IS Integrated Headset The ultra-light FSA Orbit IS Integrated Headset weighs only about 62 grams thanks to its minimalist integrated design. Apart from two angular contact bearings, a crown race, and an alloy top cover, there isn't much else to it, so there's not anything to weigh! High quality bearing seals ensure durability. This headset is for the 45mm OD headtube, and is 1-1/8", 36 degrees/ 45 degrees ACB. FSA Orbit IS Integrated Headset Specifications: Bearing type: Cartridge Crown race: 30 S. H. I. S lower: IS41 S. H. I. S upper: IS41 S. H. I. S. stem clamp diameter: 28. 6mm Stack height: 15. 7+1=16. 7mm Weight: 62 grams | Fsa | Orbit Is Integrated Headset | Black | 1 1/8", 36/45