We claim the ornamental design for a hair dryer, as shown and described.
FIG. 1 is a front perspective view of the hair dryer design;
FIG. 2 is a rear perspective view of the hair dryer of FIG. 1;
FIG. 3 is a front view of the hair dryer of FIG. 1;
FIG. 4 is a rear view of the hair dryer of FIG. 1;
FIG. 5 is a right side elevation view of the hair dryer of FIG. 1;
FIG. 6 is a left side elevation view of the hair dryer of FIG. 1;
FIG. 7 is a top view of the hair dryer of FIG. 1; and,
FIG. 8 is a bottom view of the hair dryer of FIG. 1.
The broken lines showing various aspects of the hair dryer in FIGS. 1-8 are for illustrative purposes only to show the placement of the claimed design and form no part of the claimed design.