The ornamental design for a retentateplate, as shown and described.
FIG. 1 is a front view of the retentate plate in an aspect of the present invention.
FIG. 2 is a rear view thereof.
FIG. 3 is a top view thereof. The bottom view on the opposite side thereof is a mirror image of the top view.
FIG. 4 is a right side view thereof.
FIG. 5 is a left side view thereof.
FIG. 6 is a front upper side perspective view thereof; and,
FIG. 7 is a rear lower side perspective view thereof.
The view labels used herein to denote front, back, top, bottom and side views are for convenience only and should not be interpreted as limiting the orientation of the retentate plate.
The broken lines in the drawings depict portions of the retentate plate that form no part of the claimed design.