Nashua 345 Professional-Grade Duct Tape is ideal for sealing HVAC duct and ventilation systems, heavy-duty repair, waterproof packaging, and a variety of other sealing and patching applications. This professional-grade duct tape features natural rubber adhesive that forms long-term, moisture-resistant bonds with most surfaces. Polyethylene-coated cloth backing delivers a smooth, consistent unwind and resists moisture, chemicals, and abrasion. Durable and strong, this tape offers the performance needed for even the toughest household and contractor applications. The tape measures 1.89 inches by 60.1 yards.