The ornamental design for a handset, as shown and described.
FIG. 1 is a perspective front view of a handset showing our new design;
FIG. 2 is a perspective rear view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is rear view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a top view thereof; and,
FIG. 8 is a bottom view thereof.
The broken line showing of the environmental structure of the handset in FIGS. 1-8 is for illustrative purposes only and forms no part of the claimed design.