a reinforced double - wall knock - down bin molded of plastic resin , comprising a pallet - base , two vertical side - walls , and two vertical end - walls . the pair of side - walls are rigidly secured to the pallet - base . the end - walls are secured to the pallet - base with a tongue and groove arrangement . the side and end wall extended plurality of members intermesh at the corner are secured by a vertical reinforcing post inserted from the bottom of the pallet - base up through the intermeshed corner members . a bottom end - rod secures the end - wall to the pallet and retains the corner posts . a reinforcing rod with end loops is molded inside the upper longitudinal portion of the double side - wall . a top reinforcing end bar inserted horizontally through the top corner side - wall interleave member and passed through the top of the inside of the double end - wall and the opposite top corner side - wall interleave and secured . the top horizontal reinforcing end bar engaged with the side - wall and molded - in side rod end loop provides internal reinforced structure protection against inward and outward forces at the corners and around the top perimeter in the critical area of abuse . the engagement of the top end bar and side rod end loop rests on top of the corner post to provide added vertical stacking strength for a stack of multiple bins . the center underside of the pallet - base has two parallel horizontal bars to limit center load sag where center load support is not otherwise provided .