ShelterLogic Grow it Organic Growers Pro Tunnel Design Round Top Greenhouse, 10 by 13 by 8-Feet Tunnel design for experienced grower, this greenhouse is ideal for growing plants, starting seeds and extending growing seasons Featuring metal Shelter Lock stabilizers for added strength and durability The frame is constructed of DuPont powder-coated 1-3/8 in. steel with Easy Slide cross rails for a snug cover fit The water-resistant polyethylene open scrim cover blocks harmful UVA and UVB rays Roll-up side panels add airflow