This is a special bearing for Giant Overdrive 2 (OD2) headsets which use a 1.25" to 1.5" tapered steerer.  The bearing has the same outside diameter as the Campy Compatible 4545 1 1/8" Headset Bearing, but has a larger internal diameter to fit the larger 1.25" steerer.

Sold individually.

Special 6 Months Guarantee:   All Monocrome^TM bearings carry a special guarantee with a 6 month no questions asked replacement.