It is also possible to fit a standard 1 18 steerer using an additional conversion crown the headsets include custom made stainless steel bearings which are replaceable the cups taper ring and crown race which is split for easy installation and removal are all machined from 2014 t6 aluminium all headsets come complete with the hed doctor sealing is achieved through an adjustable taper ring cover and integrated rubber seal the bearings also incorporate their own sealing and being made