1-1/8", 45° x 45° servicable ACB (campag). For 46mm OD headtube. 1-1/8" steerer. Campag compatible bearings (Yellow Seal). 7075T6 crown race. Stack height: 8.5 + 0.9 = 9.4mm.
Best Price: £23.99 from Merlin Cycles
FSA Orbit CE Headset – Black / Integrated / 1 1/8th Reviews