Description PTO clutch disc. Tractors: 77, Super 77, 88, Super 88, Super 99, 770, 880, 1550, 1555, 1600, 2-62. 7 dia., 1 hub. 12 spline, organic lining. Replaces 1KS1656. This item is a suitable alternative for the following: 156086AAF, 144-156086AAF, 1KS1656, A156086A, A-156086A, 786675