Cast Iron Dampers are used in fireplace to burn efficiently and cleaners are essential in keeping a home's air-quality at an exceptional level. It also assists in preventing heat loss when the fireplace is not in use. It has a jagged shafted handle running to the middle of the valve plate and actually work like a ratchet system, similar to a gear. The handle is grabbed at the bottom, moved towards the front of the fireplace and then pushes the hands upward in a partial angle towards the back. It is then laid back down to engage a tooth in.