OSI HM270 Construction Silicone Sealant is a medium modulus, one-part RTV silicone sealant designed for glazing and sealing. It cures at room temperature upon exposure to moisture in the air providing good tensile strength and excellent adhesion, usually without the use of a primer, to most nonporous building materials. It forms a permanent watertight and weatherproof bond to materials like glass, ceramics, aluminum, primed steel and some plastics. OSI HM270 is primarily used for structural or conventional type glazing and curtain wall sealing involving glass, plastic or metal. For general usage, OSI HM270 has many applications including sealing skylights, solar panels, ventilators, aluminum siding and windows, heating/air conditioning units, duct work, recreational vehicles, and other glass, plastic or metal assemblies. OSI HM270 offers superior elasticity and long-life reliability.