The ornamental design for a storageunit, as shown and described.
FIG. 1 is a front perspective view of a storage unit showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a rear elevational view thereof;
FIG. 6 is a top view thereof;
FIG. 7 is a front perspective view of the storage unit shown in FIG. 1 in an open position;
FIG. 8 is a front perspective view of the storage unit show in in FIG. 1 in an open position with the pallet removed;
FIG. 9 is a front perspective view of the storage unit show in in FIG. 1 in an open position with the pallet removed and the secondary storage drawer open; and,
FIG. 10 is a front perspective view of the storage unit shown in FIG. 1 installed behind a row of aircraft passenger seats.
The objects shown in dotted lines depict environment and form no part of the claimed design.