Round Stock - Trailer Axle Spindle With 4-Hole Flange - 1-3/8 Inch to 1-1/16 Inch I.D Bearings 1.376" diameter inner bearing surface - 1.061" diameter outer bearing surface 1" diameter mounting surface - 4-hole flange for mounting brake backing plate Capacity 1,750 lbs - Thread 1"-14 Inner/outer bearings, seal not included - Nut, washer and cotter pin are included Read product description below for more information