OCT 03-4100 - DRIVE COUPLER 10 SPLINE CHEVY 85-67
Steel Chevy Drive Flange/Crank Coupler, 6 bolt pattern for 2 piece rear main crankshafts. Fits Bert and Brinn transmissions.

OCT 03-4120 - DRIVE COUPLER CHEVY 86 AND NEWER 1 PC REAR MAIN SEAL
Steel Chevy Drive Flange/Crank Coupler, 6 bolt pattern for 1 piece rear main crankshafts. Fits Bert and Brinn transmissions.