8x12x2.5 Open (MR128) Halo bearing by Avid Racing Concepts is a high quality steel/chrome bearing with no shields/seals. These bearings have been tested and proven by many racers.
Bearing Dimensions
METRIC: 8mm (Inner) x 12mm (Outer) x 2.5mm (Width)
STANDARD: 0.31496" (Inner) x 0.47244" (Outer) x 0.09843" (Width)