The DS5 Oil-Based Duct SealCompound seals irregular openings to protect from air, dust, or water while providing vibration dampening properties. The non-hardening sealant adheres to metal, masonry, wood, or plastic. Duct Sealant is non-corrosive, non-toxic, contains no asbestos, and will not stain or harm the users hands. Safe and easy to use with no unpleasant odor. Maximum temperature rating of 210F (99C). Dielectric strength: 200 V/Mil. Color Dark Gray/Green. 5 pounds.