An adjustable shelving rack and system for storing and maintaining a plurality of item containers within a shelving unit in a stacked, vertical configuration. Each of the plurality of adjustable shelving racks are selectively coupled to a horizontal traverse of the shelving unit at a user determined position. The item containers may then be inserted by disposing each item container on one of a plurality of supports within each shelving rack. By having two shelving racks in close proximity to one another, each item container may be held in a suspended configuration with either side of the item container supported by a different shelving rack. Each shelving rack is coupled to a plurality of traverses through a corresponding plurality of vice assemblies which are selectively actuated to grip or apply a squeezing force to each traverse.