Start your own backyard greenhouse with Palrams Gambrel XL 12 x 12 Greenhouse. 8.5 height allows plenty of headroom for taller leafy plants. Wide, ramped entrance for wheelbarrow access. Four adjustable windows allow excellent ventilation. Durable aluminum frame and galvanized steel base support the clear, polycarbonate panels. Lockable double doors. Dimensions: 12L x 12W x 8.5H. Cancer and Reproductive Harm- www.P65Warnings.ca.gov. Color: Silver. Type: Greenhouses.