We claim the ornamental design for the retractable marking pen, as shown and described.
FIG. 1 is a front elevational view of the retractable marking pen showing our design with the point in the retracted position, the back elevational view thereof being a mirror image of the front elevational view thereof;
FIG. 2 is a left side elevational view thereof;
FIG. 3 is a right side elevational view thereof;
FIG. 4 is a top view thereof;
FIG. 5 is a bottom view thereof;
FIG. 6 is a front elevational view of the retractable marking pen with the point in the extended position; and,
FIG. 7 is a perspective view of FIG. 1 with the point in the retracted position.
The stippling shown on the grip of the pen barrel represents a surface texture.