1-4/5"(1.8") E-bike headset bearing ACB619H8K, interchange with FSA# TH MR229 bearing.
ACB619H8K = TH MR229(50x61.9x8mm, 36°x45°)
ID: 50.00mm
OD: 61.90mm
Width: 8.00mm
Inner ring angle: 36degree
Outer ring angle: 45degree