Bearing Enduro Bearings ACB 4545 4252 Stainless Steel 1-1/2" ACB 4545 4252 Stainless Steel 1-1/2"
Headset bearing, 42x52x7 mm...
Headset bearing, 42x52x7 mm (45x45o). This size bearing is also known in the bike industry by these part numbers: AC4252. Used as an upper bearing for Acros headsets.