Originally developed for military use during World War II, duct tape is one of the most versatile adhesive substances on the market today. Suitable for use in the home, in a garage or on any construction site, people use it for making repairs, seaming, sealing storage boxes and much more. Military personnel found this product came in handy for sealing ammunition cases to keep the contents dry. The same characteristics that made it effective for sealing boxes also allowed soldiers to make quick repairs to damaged weapons, vehicles and aircraft in the field. The lightweight rolls tucked conveniently into a pocket or rucksack within easy reach at a moment's notice. This industrial strength adhesive is just as useful to construction workers on any job site. Industrial strength silver cloth tapes are highly adhesive to most surfaces and are used for seaming and repairs of all kinds. This flexible adhesive wraps easily around curved surfaces and holds tight. Not all tapes are identical. Some are coated with polyethylene. Others are aluminum or metalized for different uses. If someone uses the wrong type to seal a heating or air conditioning system, it can catch on fire and produce a toxic smoke that is harmful to occupants. Any products used in these capacities must be safe for the application and will carry the Underwriters Laboratories Inc. Logo as proof it is not flammable and does not pose a safety risk.