Get World Flex Insu insulation for air conditioning ducts with a diameter of 3/8 inch and a width of 3/8 inch. This insulator is designed to provide effective protection for air conditioning and refrigeration ducts against thermal leakage and moisture. Brand: World Flex Insu. Diameter: 3/ 8 inches. Width: 3/8 inches. Use: Used to insulate and protect air conditioning and refrigeration pipes. Material: Made of high-quality insulating materials to ensure effective insulation.