The ornamental design for a percussionmallet, as shown and described.
FIG. 1 is a perspective view of a percussion mallet according to the present invention showing the mallet tethered to a cable;
FIG. 2 is a front elevation view of the percussion mallet of FIG. 1, the rear elevation view, the left side elevation view, and the right side elevation view being identical to the front elevation view;
FIG. 3 is an enlarged top plan view of the percussion mallet of FIG. 2; and,
FIG. 4 is an enlarged bottom plan view of the percussion mallet of FIG. 2.
The broken lines are for illustrative purposes and represent environmental structure and unclaimed portions of the invention and therefore form no part of the claimed design.