J'B Aviation Services' air-a-plane insulated duct heating and air-conditioning duct offers a premium product at a competitive price. The flat duct allows it to be flattened and rolled-up when not in use. The construction consists of 18 oz outer vinyl coated fabric, 11 oz inner vinyl coated fabric and a moisture-proof aluminum sided bubble wrap insulation. Attachment of ducts is done with Velcro strips. The closure design of this hose is so unique that it is patent pending!