This is a hybrid mount that is made from steel and aluminum, the top portion that mounts to your truck frame is made from ¼" thick steel and comes in our Tuff Coat Black Finish. The bottom part that holds your Speed Dolly is made from 3/16" thick Aluminum and can be adjusted to fit all 4:80 x 8 tires. We also designed an integrated latch system that can be locked with a pad-lock to keep your Speed Dolly Secured. The Car Carrier Dolly Mount is sold each and is designed to hold the In The Ditch Brand, Speed Dolly. To make a set, order two.