Trailer Axle Kits 4 On 4 Inch Trailer Hub Kit and 1 Inch Round BT8 Spindle with Trailer Bearing Kit 2 Set Specification: Axle shaft dia: 1-1/2 inch steps down to 1 inch at bearings Axle shaft overall length: 8-1/4 inch Hub stud length: 1-3/16 inch Stud size: 7/16 inch Hub dia: 5-1/2 inch Round BT8 spindle length of 8.75 inch Feature: 1,250 lb hub capacity, replacement for 2,000 lb axle Trailer hub kit is made of stainless steel material, sturdy and long-lasting Package Includes: 2 x 4 on 4 inch shaft holders 2 x 1 inch BT8 round spindles 4 x L44643/L44610 2 x 12192TB 2 x rubber plug dust covers 8 x 1/2 inch-20 nuts 4 x cotter pins 2 x spindle nuts & spacers