Caterpillar Clutch Half, p/n’s 6B0669 and 6B-0669. Twin Disc 5752. NSN 2520-00-363-9041. 37351D. 391645R1. Current price from Cat is $300.40, too SPECS: MRC Parameter Characteristics ABHP Overall Length 0.563 inches nominal ABSA Spline Quantity 20 AGZD Bore Shape Involute spline BTDH Jaw Circle Outside Diameter 10.000 inches nominal BTDK Jaw Circle Inside Diameter 4.250 inches nominal CBBL Features Provided Bore counterbore STYL Style Designator Driven jaw 15338 R3B6