Safely Sealed for Life® Providing superior products and engineered solutions to ensure the sustainability of your HVAC system. Our formulations include U.L. listing, U.L. GREENGUARD Gold certification, True Zero VOC content and 10 Year Warranties. Duct Sealing and Airflow Management systems that exceed industry standards and are engineered to ensure fast, consistent, and accurate installation. Our products and solutions deliver maximum efficiency, unparalleled quality, and unmatched savings, and to ensure these goals are met, we provide thorough training and field support.

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Duct-Seal 321

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Product Details

Duct-Seal 321 in an all purpose industrial grade duct sealant for all types of metal duct, glass fiber duct board, and flex duct, as well as duct fabric and flexible tubing runouts. It includes UV inhibitors for extended outdoor exposure and built-in fiber reinforcement for added strength. This non-toxic water based product is solvent free and is suitable for residential use. -Duct-Seal 321 is UL 181 B-M Listed -Passes ASTM D-2202, ASTM C-731. USDA, EPA and FDA Approved. LEED compliant SCAQMD Rule 1168. -City of Los Angeles Approval RR #8069