FIG. 1 is a front perspective view of a thermostat showing a new design for a thermostat device; FIG. 2 is a rear perspective view of the thermostat of FIG. 1. FIG. 3 is a front view of the thermostat of FIG. 1; FIG. 4 is a rear view of the thermostat of FIG. 1; FIG. 5A is a top view of the thermostat of FIG. 1; FIG. 5B is a bottom view of the thermostat of FIG. 1; and, FIG. 6 is a left side view of the thermostat of FIG. 1.