Exterior material: heavy duty 600d oxford cloth. inner lining material: 100% highly reflective water-proof mylar * Frame material: firm powder coated metal. removable reflective floor pan. * Built-in large door for setting up lighting system and moving plants in or out. built-in zippers for easily setup and take down * Removable roof cross members make it easy to adjust lights and accessories * 4 - (24 x 8-inch) lower ventilation slots that can be covered or opened. 2 - (3-inch diameter) utility slots. 1 - (6-inch) diameter ventilation slot.