Heavy duty ubolt plate set for Spring Under Axle suspensions. Oval bolt holes allow it to fit an axle from 2.5 to 3.5" in diameter, so if you upgrade axles you won't need new U Bolt Plates. It is also set up for 3 different mounting position options so wheelbase can be adjusted an inch either direction. Made from 3/8" thick steel plate. Bottom plate acts as a skid to help keep ubolts from hanging on obstacles and getting mashed up.