[Practical Desing] The bottom of the trailer stake bag is designed to prevent the boards from sliding, rounded corners to prevent cuts.Trailer piles give you additional transportation space,Perfect for Flatbed Truck,Utility Trailer,Barn Door,Flat Wood Fence. [Product Size]Our trailer stake pocket accommodate standard 2inch x 4inch lumber on the market. [Solid Steel Plate]Trailer side brackets made of high quality heavy duty steel, coated,no easy rust.no deformation,sturdy and solid. [Convenient to Install] truck bed rail brackets have predrilling holes on both ends, easy to install and remove, you do not need to drill, slide right into opening, providing you a lot of convenience.