The Centrifugal Clutch is ideal for three wheeler, ATV's, LTV's, GO KARTS, and other transportation vehicles. 1x Centrifugal Clutch 25.44mm 8HP-16HP as picture show. Clutch Bore: 1" (25.4mm). Fit Engines: 8HP-16HP engine, 1" (25.4 mm) Bore with 1/4" (6.35 mm) flat key way.