Arlington DSC5  5-Pound Duct Seal Compound, Non-Drying, Non-Toxic, Permanently Soft, 1-Pack
Arlington DSC5-1 Duct Seal Compound, 5-Pound will help you get the job done in no time. The duct seal compound is non-drying and will stay permanently soft and pliable. The duct sealing compound will not corrode plastic materials or metals. In addition, have more peace of mind knowing this duct sealing compound is non-toxic and asbestos-free. Arlington's ducting compound will adhere easily to most clean, dry surfaces.