CIS now proudly offers CPVC duct online! This 16" size duct is great fo air handling systems and can handle temperatures of up to 200 degrees Fahrenheit. Need fittings? We also carry a huge selection of CPVC duct fittings. Everything you need to make your project a success. Call today for a quote or submit a form online. Size: 16", Material: CPVC, O.D.: 16.000", Wall: .187", Std Length: 10 or 20 ft. Standards: ASTM D1784