Enduro Trek speed concept upper headset bearing 14.2mm inside x 25mm outside x 6.5mm wide 45 x 45 degree, This size bearing is also known in the bike Industry by these part numbers: 307481, W 276442
Headset bearing with an internal angle 36 degrees and external angle of 45 degrees 40.0mm inside x 51.8mm outside x 8.0mm wide, also known as ACB518K, MR110, TH-073, TK518B