FIG. 1 is a perspective view of a set of bristles for a toothbrush showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a left side elevation view thereof, the right side elevation being a mirror image of the left side elevation as shown herein in FIG. 3;

FIG. 4 is a front end elevation view thereof; and,

FIG. 5 is a back end elevation view thereof.

In the various figures, the body of a toothbrush or a portion thereof is shown in broken lines for illustrative purposes only and forms no part of the claimed design.