The ornamental design for a supportpad, as shown and described.
FIG. 1 is a top-front-left perspective view of a support pad showing our new design;
FIG. 2 is a bottom-rear-right perspective view thereof;
FIG. 3 is a top plan view thereof;
FIG. 4 is a bottom plan view thereof;
FIG. 5 is a left-side elevational view thereof, the right-side elevational view being mirrored thereto;
FIG. 6 is a front elevational view thereof;
FIG. 7 is a rear elevational view thereof; and,
FIG. 8 is top-front-left perspective view thereof, wherein the support pad is shown coupled to an exemplary second iteration of the present invention with an exemplary clamp.
The dashed line showing the exemplary clamp and pad in FIG. 8 is included for the purpose of illustrating environmental structure and forms no part of the claimed design.