FIG. 1 is a front elevational left hand perspective view showing the switch unit of our new design;

FIG. 2 is a front view thereof;

FIG. 3 is a left side view thereof, the right side view being the mirror image thereof;

FIG. 4 is a rear view thereof; and,

FIG. 5 is a rear perspective view thereof.

The aspects of the design shown in dotted lines do not form a part of the claimed design.