The ornamental design for a seawallcap, as shown and described.
FIG. 1 is a perspective view of a sea wall cap;
FIG. 2 is an end view thereof; the opposite end being a mirror image;
FIG. 3 is a side elevation view thereof;
FIG. 4 is a top view thereof; and,
FIG. 5 is a bottom view thereof.
Shading shown in the figures is for illustrative purposes to show surface contours in the drawings only and forms no part of the invention.
The sea wall cap is shown with a symbolic break in its length. The appearance of any portion of the article between the break lines forms no part of the claimed design.