This Trailer Single Axle Double Eye Leaf Spring Hanger Mounting kit comes with everything you need to attach your double eye leaf springs to your trailer. In this kit you will receive (2) weld on front hangers and (2) weld on rear hangers designed to be used with a 1 3/4 inch wide double eye trailer leaf spring. This hanger kit also includes (4) Leaf Spring shackles that have a center hole to center hole measurement of 3 1/8 inches and (6) leaf spring mounting bolts that are 9/16 inch diameter and 3 inches long.