This is a laser cut kit to make a 1:48 scale 18' long x 3' wide (4.5 x .75 actual inches) arched bridge with railings as shown. 

Please note that the part carrier sheet should not be discarded until after assembly as it includes four slots which will hold the arched stringers in alignment, allowing you to position the planks quickly. The railings are three pieces each, composed of the main center segment and two side pieces, then the completed railing assembly is glued to the arch assembly. Some tape and small right-angle blocks are suggested for ease of building.