The ornamental design for a hairtreatmentdevice, as shown and described.
FIG. 1 is a left side perspective view of a hair treatment device embodying my new design, with the hair engaging surfaces of the device shown in closed position and a protective cap placed over the distal tips of the hair engaging surfaces;
FIG. 2 is a left side perspective view of the invention, with the protective cap removed and the hair engaging surfaces of the device shown in open position;
FIG. 3 is a left side elevation view of the device as shown in FIG. 1;
FIG. 4 is a right side elevation view of the device as shown in FIG. 1;
FIG. 5 is a top plan view of the device as shown in FIG. 1;
FIG. 6 is a bottom plan view of the device as shown in FIG. 1;
FIG. 7 is a front end perspective view of the device as shown in FIG. 1; and,
FIG. 8 is a rear end perspective view of the device as shown in FIG. 1.
For convenience of illustration, the protective cap of the hair treatment device has been removed in FIG. 2.