Walk-in Polycarbonate Greenhouse Green House with Automatic Temperature Window and Lockable Door, 6.5' x 4' x 6.7'Heavy Duty Greenhouse: Our polycarbonate greenhouse is reinforced with a strong varnished wood frame to add extra endurance. Insulating twin wall polycarbonate lets in sunlight while stopping scorching UV to keep plants comfy in all sorts of weather. Automatic Vent: Take control of heat with a set it and forget it solution. The large side window of our backyard greenhouse vents away old air to fine tune the interior to your plants' needs