US D555021 S1
The ornamental design for a diagnostic meter, as shown and described.
FIG. 1 is a front perspective view of the diagnostic meter of our new design;
FIG. 2 is a rear view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a left side view thereof; and,
FIG. 6 is a top view thereof.
The bottom of our diagnostic meter is not visible during normal use and does not form part of the claimed design.