Material upgrade of high strength steel, durable. Black baking varnish with exquisite surface, delicate color and smooth touch. The upgraded clip bar ensures the stability of books. Free expansion, foldable, less than 80CM, up to 170CM. The footsteps are connected by two pieces, and from then on they will no longer fall back and fall over. It is suitable for the practice and performance of various musical instruments. It can be folded and carried easily. Suitable for all kinds of height, children, adolescents and adults. Strong workmanship, durability, standing and sitting can be.