FSA Orbit MX Headset The FSA Orbit MX headset is an affordable, easily serviceable headset for conventional straight head tubes. Dual seal, angular contact bearings provide long lasting, smooth rolling performance. The headset is forged from CNC machined 6061 T6 aluminum. Features FSA's core line of headsets that have become an industry benchmark Dual seal, angular contact bearings provide long lasting, smooth rolling performance Forged and CNC machined 6061 T6 alloy cups | Fsa | Orbit Mx Headset | Black | 32. 4, 1 1/8