Multi-layer grinding disc

FIG. 1 is a front, top, right side perspective view of a multi-layer grinding disc, showing our new design;

FIG. 2 is a back, bottom, left side perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a back elevational view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a right side view thereof;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a bottom plan view thereof.

The broken lines shown in the drawings depict portions of the multi-layer grinding disc that form no part of the claimed design.