Short depth idler hub kit has 5 on 4.5" bolt spacing. Specialty hub for 2000lb rated axles. This hub has a 1 5/8" measurement between the races inside the hub and a 5.5" Flange measurement. Comes with inner and outer bearing (L44649), standard grease seal, standard dust cap, and 5 lug nuts. Commonly used on older boat trailers.