A premium quality 100% silicone sealant that stays permanently flexible. Suitable for sealing around windows, flues on gas appliances, joints and metal stacks and ductwork. An excellent gasket maker to replace existing cork and felt rubber. Ideal for holding gaskets around stove and fireplace doors. Oxygen sensor safe. Withstands continuous temperatures up to 260°C (500°F) with peak at 316°C (600°F).