FIG. 1 is a front, top perspective view of a first embodiment of a heater showing the new design;
FIG. 2 is a rear, bottom perspective view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a side elevational view thereof;
FIG. 6 is a side elevational view from the side opposite to that of FIG. 5;
FIG. 7 is a top plan view thereof;
FIG. 8 is a bottom plan view thereof;
FIG. 9 is a front, top perspective view of a second embodiment of a heater showing the new design;
FIG. 10 is a rear, bottom perspective view thereof;
FIG. 11 is a front elevational view thereof;
FIG. 12 is a rear elevational view thereof;
FIG. 13 is a side elevational view thereof;
FIG. 14 is a side elevational view from the side opposite to that of FIG. 13;
FIG. 15 is a top plan view thereof; and,
FIG. 16 is a bottom plan view thereof.
The broken lines in the figures depict portions of the heater that form no part of the claimed design. The dot-dash-dot broken lines denote the boundaries of the claim and form no part thereof.