The HS-B-21 BMC replacement headset kit includes FSA standard bearings, an alloy compression split ring, the URS 1"1/4 ICS top cone, and 3 spacers. This kit contains: MR170{070E-RS} lower bearing | MR136 upper bearing | alloy compression ring | ICS top cone for 1"1/4 steerer (Classic 1”1/4 - 60x47-25) | 3x 10mm alloy spacers