Quality Material: This Boat Trailer Bunk Brackets are made from quality galvanized steel, which is wear resistant and sturdy for long term use.Complete Set: The Boat Bunk Brackets set includes 8 brackets, 4 U Bolts, 24 Spacers, 8pcs O Rings,12 Nuts, and 12 Screws to meet your installation needs.Easy to Install: These Boat Trailer Parts are easy to install. The U Bolts can be easily fixed on the boat and trailer while the spacers and nuts can secure the brackets in place for convenient usage.Wide Application: This Boat Trailer Rack is nice for use in both seawater and freshwater environments. It's suitable for a 3"x3" , 2"x3", and 1.5"x3" trailer crossbeams, Boat Trailer Crossmember, Fishing Boats, Sailboats etc.Practical Accessory: This Boat Trailer Bunk Shelf Holder serves as a practical tool for fixing, repairing, or replacing old damaged parts. Specification: Material: Galvanized Steel Size Chart: ?Length: 20cm/7.87inch Package Includes: 8 Brackets,4 U Bolts,24 Spacers,8pcs O Rings,12 Nuts,12 Screws Note: Please allow slightly errors 1-2cm differences due to manual measurement.