Fsa orbit xtreme pro 15 reducer headsethigh quality fsa new school approach to the reducer headset away with the conventional 15 headset fsa have introduced this as a more solid option reducing the need for spacers and cups adding more weight to your ride features new for this year 15 to 1 18 industrial bearings fsa logo detailing reduction design forged and cnc machined 7075t6 aluminium cups 21mm headtube insertion industrial cartridge sealed bearings stainless steel crown race stack