This sprocket hub Is great for converting your mini bike or go kart to the split sprockets. This will allow quick gear ratio changes with out removing the axle. This sprocket adapter fits the Monster Moto 80cc/105cc, Motovox, Doodlebug and Baja mini bikes with the 6 bolt hole pattern on the wheel. It will also fit any wheel that has a 2 7/8" hole pattern for the existing sprocket. Made from 6061-T6 aluminum OD: 5.875" Center Hole: 1.47" Machined Shoulder: 4.562" Outside Hole pattern for sprocket: 5.25" with 1/4-28 threaded holes 4 Hole pattern: 2.875" 6 Hole pattern: 1.968" 6 1/4-28 bolts and nuts included.