To suit 1 1/8" forks Upper cup Stack height: 11mm - Total upper stack height including bearing cover: 16mm Lower cup Stack height: 3mm Upper Bearing: 41mm OD, 45 x 45 Degree AC sealed bearing Lower Bearing: 41mm OD, 45 x 45 Degree AC sealed bearing Split type 7075-T6 aluminium crown race for simple, tool free installation Headset comes complete with top-cap (star-nut included), bearings and crown race - all parts required for fitment