Rigid Hitch Trailer Hub Kit (BT-150-04-A) 5 Bolt on 4-1/2" Bolt Circle with 1 Inch I.D. Bearings Fits 2,000 lb. axles with 1" straight spindle Complete assembly with bearings, seal, dust cap, cotter pin and lug nuts Measures 4-1/4 inches tall (through center of hub) 2,000 lb capacity - 1/2-20 thread - 5 bolt on 4-1/2 inch bolt circle Read product description below for more information