We claim the ornamental design for a pilaster for a partition system, as shown and described.
FIG. 1 is a perspective view of a design for a pilaster
FIG. 2 is a front view of the design of FIG. 1, the rear view is a mirror image of FIG. 2.
FIG. 3 is a left side view of the design of FIG. 1, the right side view is a mirror image of FIG. 3; and,
FIG. 4 is a section view of the design of FIG. 2 taken along line 4-4.
The ornamental design which is claimed is shown in solid lines in the drawings. Only a portion of the outer surface of the pilaster is being claimed. No part of the interior of the pilaster is being claimed. The broken lines and non-shaded areas in the drawings are for illustrative purposes only and form no part of the claimed design.