SB-4400 PERMA-SEAL™ Invisible Penetrating Sealer is a penetrating, breathable silane/siloxane blend solvent based sealer that protects horizontal and vertical surfaces from water penetration and salt damage from the use of de-icers or exposure to salt air. SB-4400 has the consistency of water and is clear in appearance when applied and dries clear with an invisible finish. Some surfaces may darken slightly. It can be used indoors (with proper ventilation) and outdoors on both new and old surfaces. SB-4400 can be applied immediately, as its unmatched breathability will not trap efflorescence. On new concrete, SB-4400 should be applied once concrete is fully cured (30 days after installation). SB-4400 requires two coats. Cured sealer is freeze resistant to -60°F (-51°C) and is stable up to a temperature of 180°F (82°C). Shipping weight is 52 lbs. Ships with a $12.00 handling fee for weighing over 50 lbs.