original c. 1900's antique american interior residential black enameled ornamental cast iron upright furnace grate or register designed and fabricated by hess warming & ventilating co., chicago, il. the grate features diamond-shaped lattice work accentuated with intricately designed filigree. the original pressed steel louver was lost long ago. mostly uniform surface black paint finish. contains four screw holes four mounting purposes. measures 13 5/8 x 10 7/8 inches.