The ornamental design for an endocone, as shown and de- scribed.
FIG. 1 is a front right side isometric view of an endocone in accordance with the new design;
FIG. 2 is a front isometric view thereof;
FIG. 3 is a rear isometric view thereof;
FIG. 4 is a top isometric view thereof;
FIG. 5 is a left side isometric view thereof;
FIG. 6 is a bottom isometric view thereof;
FIG. 7 is a right side isometric view thereof.
FIG. 8 is an enlarged front isometric view of an attachment piece of the endocone of FIG. 1, with other parts of the endocone omitted for ease of illustration;
FIG. 9 is a rear isometric view thereof;
FIG. 10 is a front right side isometric view thereof;