Spider Workhorse 2 Swivel on the post - 4" Post

10-1/2″ x 14-1/2″ x 1/4″ aluminum formed slide plate. Swivel locks and clamps tight to 4″ post for rock solid performance. Heavy-duty stainless steel lock pin. Large easy-to-reach control knobs. The slide travels 6″ fore and aft.