Top sealing dampers are the open and shut solution to replace worn out fireplace throat dampers. Mount on top of the flue tile or directly on the chimney crown, Cast aluminum includes all mounting hardware and a 32 ft. stainless steel cable. Seals out animals, birds, insects, leafs, rain and snow. Prevents heat and air conditioning loss when closed. Fits 8 x 8 flues from:6" x 6" to 9" x 9". Lifetime Warranty.