Supine Board

FIG. 1 is a front, left and top perspective view of a supine board showing my new design. FIG. 2 is a rear, right and bottom perspective view thereof. FIG. 3 is a front view thereof. FIG. 4 is a 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 lines in the drawings illustrate portions of the supine board that form no part of the claimed design.