The spare tire wall mount bracket is made of 3.0mm Steel. The surface Finish is black power coating.This product is strong and durable to prevent rust damage to the spare tire.After installing this product you can mount the spare tire directly on the wall of the enclosed trailer, preventing the spare tire from bouncing, saving space in the car, easy to repair and transport the spare tire.Easy to install, just drill holes and hook the spare tire to the trailer wall. Package includes 1 set of spare tire wall mount bracket (As the picture shows). Aftermarket fit for most sizes of wheels.(We are equipped with two different sizes of bolts, the long bolt size is 3.94 inch and 5.91 inch, you can choose according to the thickness and weight of the tire).