Three Adjustable Height Settings: The 3 heights are about 21inch, 24inch, 27inch. Superior strength and durability: surface is slightly textured to avoid scratching and is smooth enough to write on. Stand steadily: Gravity slide lock for extra stability, will not wobbly when you use it Material: Aluminum, durable, green environmental and recycled material HDPE 4.Light-weight: Made of lightweight aluminum, easy to carry for camping, picnic, indoor or outdoor entertainment activities and so on, do not take up so much room.