Premium quality 100% silicone sealant that stays permanently flexible. Suitable for sealing around oven windows, flues on gas appliances, joints and metal stacks and ductwork. Excellent gasket maker to replace existing cork and felt rubber. Ideal for holding gaskets around free standing wood heaters and zero clearance wood inbuilts doors. Oxygen sensor safe. Withstands continuous temperatures up to 343°C(650°F).