FIG. 1 is a perspective, rear view of a foot spa showing my new design;
FIG. 2 is a perspective, front view thereof;
FIG. 3 is a perspective, right side view thereof;
FIG. 4 is a perspective, left side view thereof;
FIG. 5 is a perspective, rear and right side view thereof;
FIG. 6 is a perspective, rear and left side view thereof;
FIG. 7 is a perspective, rear, left-side view thereof shown in an environment of use;
FIG. 8 is a perspective, rear, right-side view thereof shown in an environment of use;
FIG. 9 is a rear view thereof;
FIG. 10 is a front view thereof;
FIG. 11 is a right side view thereof;
FIG. 12 is a left side view thereof; and,
FIG. 13 is a top view thereof.
The broken lines in FIGS. 1-13 illustrate portions of the foot spa that form no part of the claimed design. The additional broken lines in FIGS. 7 and 8 illustrate environmental subject matter and form no part of the claimed design.