High-strength Ductmaster™ nylon duct straps come in various sizes up to 48-in. long. The straps are molded from type 6/6 nylon and feature a head design that lets the strap easily slide in place, requiring low insertion forces, to speed installation, the company says. Providing a 200-lb average loop tensile strength to prevent breakage when tightening securely, the straps are suitable for installing ductwork or hose up to 15-in. od.