This fire blanket can be placed on a fire screen at night to keep warm air in and block out the cold. This blanket saves energy and money by reducing heat loss from the chimney after a wood burning fire. pavenex is a fire resistant carbon fiber material. It attaches to your metal screen with heavy-duty magnets. This will ensure that heat will remain in your home when the fire has diminished to residual embers. This blanket is also great for winter when there is no fire. It helps keep the warmth in the home instead of leaking out the chimney.