BPB-5005 Universal GM 11-5/8'' Rear Brake Rotor Replacement vented iron 11-5/8" O.D. brake rotor for GM rear axles. Center Hole: 2.782" Backspace: 1.75" Thickness: .782" Axle Flange Maximum Diameter: 6" Bolt Pattern: 5 on 4-3/4'' Sold Individually