If you own a Majestic fireplace or stove, you already know that you are getting first-rate performance and safety from your product. Still, other steps must be taken to keep your home safe, and the Majestic DVP-WS Wall Firestop - 5 Inch Diameter will help bring your fireplace up to full safety code. Your walls are made of combustible material, and the ventilation pipe must pass super-heated air through the wall and out of your home. A firestop will prevent that pipe from endangering your walls, and the 3 firestop wont take away from the visual appeal of your stove. This unit weighs 1 lb. and is sold separately.