| 主权项 |
1. A system comprising:
a rectangular frame structure comprising a closed bottom interior section; at least two shelving elements affixed to at least two interior walls, the at least two shelving elements spaced a distance from the bottom of the interior section, the at least two shelving elements each comprising at least one orifice; at least two upper retaining elements affixed to at least two interior walls, the at least two upper retaining elements spaced a distance from the at least two shelving elements, the at least two upper retaining elements each comprising at least one orifice, a platform comprising a top surface and a bottom surface, at least a portion of the platform encompassed within an open interior space between the at least two shelving elements; at least two pin collars affixed to the platform, the at least two pin collars each comprising hollow interior portions; a hitch base portion pivotable about a pivot axis, the hitch base portion comprising a hollow interior portion, the hitch base portion comprising a hitch platform affixed to a top portion of the hitch base portion; a pivot pin rotatable within a portion of at least two of the hollow interior portions of the at least two pin collars and the hitch base portion; a lock bar slidably engageable within the distance between the at least two shelving elements and the at least two upper retaining elements, the lock bar comprising at least two orifices; and a plurality of locking elements partially encompassed within the at least one orifice of each of the at least two shelving elements, the at least one orifice of each of the at least two upper retaining elements, and the at least two orifices of the lock bar. |
