The Topstar Sitness Bob standing stool is a real ergonomic highlight in the field of active sitting. The tiltable seat keeps the lower back in constant motion, which has a back-strengthening effect. The benefits are obvious, or rather entirely on the owner's side: back pain and stiffness are a thing of the past, replaced by greater physical health. The secret behind the success of this product is the novel 'run-flat' tire - a non-inflated base made from a special TPU (thermoplastic urethane) material. TPU is a robust plastic that is still flexible enough to take on new shapes. We use TPU to give hard materials their special 'dexterity'. The ergonomic Sitness Bob standing stool increases well-being and improves performance in the workplace! Design: Thomas Walser Material: Aluminum, rubber, TPU (thermoplastic urethane) Seat dimensions: 49-70h x 36.5w cm Technical features: ergonomically shaped seat, three-dimensionally movable seat, seat height adjustable.