The ornamental design for an insulated cover for sprinkler backflow assembly/valves, as shown and described.
FIG. 1 is a right side elevation view of an insulated cover for sprinkler valves particularly suited for back flow valves showing my new design, the left side elevation view being a mirror image of that shown;
FIG. 2 is a top plan view thereof;
FIG. 3 is a bottom plan view thereof;
FIG. 4 is a left end elevation view thereof, the right end elevation view being a mirror image of that shown; and,
FIG. 5 is a top left end perspective view thereof, the broken line disclosure being a sprinkler backflow assembly for illustrative purposes only and forming no part of the claimed invention.