The ornamental design for a horizontalmoldingsystem, as shown and described.
FIG. 1 is a perspective view for a horizontal molding system;
FIG. 2 is a front view for a horizontal molding system;
FIG. 3 is a back view for a horizontal molding system;
FIG. 4 is a side view for a horizontal molding system;
FIG. 5 is a top-down view for a horizontal molding system;
FIG. 6 is a perspective view for a horizontal molding system depicting the horizontal molding system containing an ice pop inside; and,
FIG. 7 is a perspective view depicting the handle for a horizontal molding system connected to an illustrative ice pop when removed from the horizontal molding system.
The broken lines shown throughout the views represent the portions of the environmental structure which form no part of the claim.