In our goal of being your best source for all things towing, the Curt line of trailer jacks is designed with care and manufactured with pride. Curt jacks are made with quality to promote the life and function of your trailer and they come in several different styles to accommodate your needs, whether you are a frequenter of the boat landing, the campground, the racetrack or the farm. This replacement jack mounting bracket is the male pipe end, intended to mount a Curt swivel jack. It allows for easy swiveling of the jack post, to be folded up and out of the way when not in use and inserts into the female pipe end #28930. It comes with a 9/16 in pin hole.