The ornamental design for a striking toolhead, as shown and described.
FIG. 1 is a perspective view of a striking tool head embodying my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left view thereof;
FIG. 5 is a right view thereof;
FIG. 6 is a top view thereof; and,
FIG. 7 is a bottom view thereof.
The broken lines within the claimed subject matter depict features of the striking tool head that form no part of the claim. The remaining broken lines represent environmental subject matter that also forms no part of the claim.