The invention is a storage unit (1 ) comprising an accumulation structure (4) defined by a plurality of vertical walls (7) provided with a plurality of guide means (8) arranged horizontally and configured so that they can support a plurality of trays (5). In each tray there is at least one shaped housing (9) that accommodates at least one object (O) and on the sides of the tray there are shaped edges (10) configured so that they can be slidingly coupled with the guide means (8) when the tray (5) is inserted between two consecutive vertical walls (7). Each tray (5) is configured so as to receive on its upper surface (5a) one or more spacer elements (15) configured in such a way that they can be superimposed to one another and to the upper surface (5a) and connected to one another and to the upper surface (5a) through removable connection means (16) in order to vary the depth (9b) of the shaped housing (9). Moving means (6) are provided that are suited to move the trays (5) with the objects (O) arranged thereon and to insert/extract the trays (5) in/from the guide means (8).
