The ornamental design for a reversiblecollar, as shown and described.
FIG. 1 is a front perspective view of a reversible collar showing my new design with an adjustable strap and hook to expand or shorten the collar length; and,
FIG. 2 is a front perspective view thereof in a reversed position.
The dashed lines on the collar represent stitching and form part of the claimed design.
The reversible collar is designed for use as a dog or cat collar.
There is an adjustable strap on one side of the collar with loops, and a hook on the opposite side of the collar to shorten or lengthen to fit the collar size on the dog or cat.