A hinge system for joining adjacent side walls (12 and 14) having a connected position and an unconnected position. The hinge system includes a hinge mechanism (16) and a latching mechanism (17) for preventing inadvertently collapse of adjacent side walls (12 and 14). The hinge mechanism (16) has a plurality of barrel lugs (20a, 20b, 20c, 20d) having a plurality of barrels (21a, 21b, 21c, 21d) and a plurality of hook lugs (22a, 22b, 22c, 22d) having a plurality of pins (23a, 23b, 23c, 23d). The hook lugs (22a, 22b, 22c, 22d) are aligned relative to corresponding barrel lugs (20a, 20b, 20c, 20d), respectively, so that the pins (23a, 23b, 23c, 23d) of the hook lugs (22a, 22b, 22c, 22d) are inserted into the barrels (21a, 21b, 21c, 21d) of a corresponding barrel lugs (20a, 20b, 20c, 20d) to join adjacent side walls (12 and 14). The latching mechanism (17) includes a finger (24) and is pivotally supported to pivot between a latched position and an unlatched position.