This is a replacement Headset Race / Lower Spacer for Specialized Stumpjumper FSR 650B models 2015+ This is compatible with the following bikes: Model Year Category Model 2017 LEVO FSR WMN LEVO FSR WMN ST 6FATTIE 2017 LEVO FSR WMN LEVO FSR WMN ST 6FATTIE NB 2015 SJ FSR SJ FSR Comp Evo 650B 2015 SJ FSR SJ FSR Elite Evo 650b 2015 SJ FSR SJ FSR Expert Carbon Evo 650B 2015 SJ FSR SJ FSR Expert Carbon Evo 650B FRM 2015 SJ FSR SW SJ FSR Carbon Evo 650b