Pure Silicone sealant is a specially formulated, neutral-cure, 100% silicone sealant for a variety of substrates such as ceramic tile, porcelain, slate, aluminum, wood, metal, glass, fiberglass, laminate, concrete, PVC and other plastics, and many other common materials. UV- and mildew-resistant Pure Silicone will not shrink or crack, providing a flexible barrier and tenacious adhesion between horizontal and vertical surfaces or any other changes in plane such as expansion joints in fixtures, tub surrounds, sinks, toilets, vanities, electrical plumbing penetrations, roofing, floors, walls, and ceilings. Pure Silicone™ conforms to TCNA Handbook EJ171, and it meets or exceeds the test requirements of: ASTM C920 Type (S) Grade (NS) Class (25), (M), (A), (G), (T), (NT), TT-S-01543A, TT-S-00230C, AAMA, 803.3, 905.2, 803.3 Type (I), 802.3 Type (II). This product is 100% waterproof, permenantly flexible, and has a movement capacity of about 25%. Best of all, it is MADE IN THE USA!