The ornamental design for a hairtowel, as shown and described.
FIG. 1 is a perspective view of a hair towel including a braided portion;
FIG. 2 is a side view of a hair towel including a braided portion;
FIG. 3 is a side view of a hair towel including a braided portion;
FIG. 4 is a top view of a hair towel including a braided portion;
FIG. 5 is a bottom view of a hair towel including a braided portion;
FIG. 6 is a rear view of a hair towel including a braided portion;
FIG. 7 is a front view of a hair towel including a braided portion;
FIG. 8 is a front perspective view of a hair towel including a braided portion in a wrapped configuration as applied to a user; and,
FIG. 9 is a rear perspective view of a hair towel including a braided portion in a wrapped configuration as applied to a user.
The broken line outlines of elements on the hair towel depict portions of the hair towel that form no part of the claimed design. The broken line outline of the partial human in FIGS. 8 and 8 assist to illustrate the hair towel in a position of use and form no part of the claimed design.