ACB MR136 Giant Od2 Upper 11/4-41.8x33x6mmPlease check precise measurements against the below to determine the correct size. SPECIFICATIONS STEERER DIAMETER: 1 1 2" OUTER DIAMETER: 51. 8mm INNER DIAMETER: 40mm HEIGHT: 8mm CHAMFER ANGLES: 36 45 TH 073E Chrome steel balls and races TH 073S Stainless balls and races TH 073R Alloy outer race, chrome steel balls and inner race Also known as part code MR 127. Black Bearing equivalent is bearing D1