General purpose, one-part silicone adhesive sealant which cures at room temperature to form a tough rubber seal.LOCTITE SI 593 is a black, general purpose, one-part silicone adhesive sealant which cures at room temperature to form a tough rubber seal. Will not slump in overhead or vertical applications. It has been formulated to withstand extreme temperature cycling, UV light, and ozone. It CANNOT be painted and is also available in clear and white.