The ornamental design for a shower head, as shown and described.
FIG. 1 is a perspective view of a shower head showing our new design;
FIG. 2 is another a bottom perspective view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a left side elevational view thereof;
FIG. 6 is a right side elevational view thereof;
FIG. 7 is a top plan view thereof;
FIG. 8 is a bottom plan view thereof; and,
FIG. 9 is an enlarged view of area 9 circumscribed within FIG. 1.
The broken lines and areas within them in the drawings depict portions of the shower head that form no part of the claimed design. The dot dash dot broken lines in FIGS. 1 and 9 denote the boundaries of the detail areas and form no part of the claimed design.