The ornamental design for a selfdrillinganti-removal screw, as shown and described.
FIG. 1 is a perspective top side view of a self drilling anti-removal screw showing my design;
FIG. 2 is another perspective top side view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a side view thereof; and,
FIG. 5 is another side view thereof.
The screw is shown with a symbolic break in its length. The appearance of any portion of the screw between the break lines forms no part of the claimed design.