ShelterLogic GrowIT Greenhouse-in-a-Box Pro, 12 x 20 x 8 ft. Heavy duty 1 3/8 in. all-steel frame, patented steel ShelterLock Stabilizers, Ratchet-Tite tensioning, and the Easy Slide Cross Rail System provide a stable and durable Greenhous Roll-up side panels and half moons screen vents at each end provide optimal airflow and temperature control Triple-layer, heat bonded Rip Stop translucent cover is waterproof and UV treated inside and out. Specifically designed translucent cover transmits light for optimal plant growth 15 in. ShelterAuger anchors come standard Peak design for growing plants, starting seeds and extending growing seasons Triple-layer, heat bonded Rip Stop translucent cover is waterproof and UV treated inside and out. Specifically designed translucent cover transmits light for optimal plant growth. Roll-up side panels and half moons screen vents at each end provide optimal airflow and temperature control. Heavy duty 1 3/8 in. all-steel frame, patented steel ShelterLock Stabilizers, Ratchet-Tite tensioning, and the Easy Slide Cross Rail System provide a stable and durable Greenhouse.