Perfect PerformanceOur aluminum butyl super waterproof seal duct tape is 48mil Thickness x 4" Width x 16.4' Length ( 1.2MM x 10CM x 5M ); Working Temperature: -40 to 248 , Elongation rate of 1000%, stop the leak effectively aging resistance for 30 years. Widely ApplicationMagic tape patch Suitable for roof leaks, window sealing, rv awning, gutters, down spouts, boats, personal watercrafts, canoes, outdoor equipment, mobile homes, RVS & campers, PVC & plumbing pipes, sprinkler systems, doors, walls, seams, vents, air ducts, HVAC systems, DIY projects, etc. Durable MaterialHeavy Duty & Strong Adhesive, seal tape is made of pure butyl rubber with upgraded aluminum foil cover, thicker and heavier than similar products, stronger adhesive, toxic-free, waterproof, UV resistant, vapor prevent, anti-aging and odorless; provides a better sealing result and longer service time. Easy To UseSimply peel off the release film and apply the butyl sealant tape to anywhere needed. For better performance, tightly press the tape to a clean and dry surface is advised; store in cool place. No need to do Extra Waterproof Coating, you will find it is EASY and EFFICIENT. Buy With ConfidenceWe stand by our commitment to quality. Any product related problem, please feel free to contact us. We will try our best to help you to your satisfaction. High-quality products and service is our priority.