I claim the ornamental design for a safety belt, as shown and described.
FIG. 1 is a front perspective view of a safety belt embodying my new design, showing the safety belt in a closed position and showing an actuator switch and a battery pack in broken lines accommodated thereon;
FIG. 2 is a rear perspective view of the safety belt showing the safety belt in the closed position and showing the battery pack in broken lines accommodated thereon;
FIG. 3 is an outer side elevation view of the safety belt showing the actuator switch and the battery pack in broken lines accommodated thereon;
FIG. 4 is a bottom view of the safety belt of FIG. 3 showing the actuator switch and the battery pack in broken lines accommodated thereon;
FIG. 5 is an inner side elevation view of the safety belt of FIG. 3;
FIG. 6 is a top view of the safety belt of FIG. 3 showing the actuator switch and the battery pack in broken lines accommodated thereon;
FIG. 7 is a left end view of the safety belt of FIG. 3; and,
FIG. 8 is a right end view of the safety belt of FIG. 3.
The actuator switch and the battery pack, shown in broken lines, forming no part of the claimed design.