I claim the ornamental design for a metal core for rubber track, as shown and described.
FIG. 1 is a front perspective view of a metal core for rubber track, showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is a bottom perspective view thereof.
One exemplary use of the metal core for rubber track embodying the ornamental design shown or described herein is for use in a heavy agricultural equipment or machine in which one or more of the metal core is fitted with rubber tracks and forms a continuous loop.