FSA, Orbit C, Headset, Black, 74g, (S.H.I.S : IS42/28.6 | IS42/30) DESCRIPTION AND MATERIALS 1-1/8", 45/45 ACB For 46 mm OD head tube 1-1/8" steerer Alloy top cover Campy angular contact bearing (yellow seal) Stack height: 15.5 mm + 0.5 mm = 16 mm Weight: 73.6 g