The Four Tier Mini Greenhouse is perfect for small patios. The lightweight skeleton of this four tier shelving system is made from coated aluminum tubing. Four laminated wire shelves fit in place, and a transparent plastic greenhouse cover fits over the whole unit. The front of the plastic has two zippers to roll the door up and tie to an open position to ventilate the greenhouse. It's useful for seed starting, as a cold frame in spring and fall, and as a greenhouse in winter - grow salad greens all winter long! Fully assembled, the Four Tier Mini Greenhouse measures 157 x 68 x 48cm (62 x 27 x 19"). This product collapses down for easy shipping and storage.