We claim the ornamental design for an end cap of a ball bat, as shown and described.
FIG. 1 is a side, end perspective view of an end cap of a ball bat of the present design;
FIG. 2 is an enlarged side, end perspective view of the end cap of the ball bat of FIG. 1;
FIG. 3 is an end view of the portion of the end cap of the ball bat of FIG. 1;
FIG. 4 is a first side view of the end cap of the ball bat of FIG. 1; and,
FIG. 5 is a second side view of the end cap of the ball bat of FIG. 1.
The ornamental design that is claimed is shown in solid lines in the drawings. The broken (dashed) lines shown in FIGS. 1 through 5 are included only for the purpose of illustrating environmental elements, and form no part of the claimed design.