The ornamental design for corner post for a collapsiblecontainer, as shown and described.
FIG. 1 is a top, front, left perspective view of a corner post for a collapsible container showing my new design;
FIG. 2 is a top plan view of the corner post for a collapsible container shown in FIG. 1;
FIG. 3 is a cross-sectional view of the corner post for a collapsible container taken at line I—I in FIG. 5;
FIG. 4 is a right side, partial elevational view of the corner post for a collapsible container shown in FIG. 1;
FIG. 5 is a front side, partial elevational view of the corner post for a collapsible container shown in FIG. 1;
FIG. 6 is a left side, partial elevational view of the corner post for a collapsible container shown in FIG. 1; and,
FIG. 7 is a rear side, partial elevational view of the corner post for a collapsible container shown in FIG. 1.
The broken lines immediately adjacent the shaded areas represent the bounds of the claimed design while all other broken lines are directed to environment and are for illustrative purposes only; the broken lines form no part of the claimed design.