The ergonomically shaped seat cushion and the pre-shaped backrest promote concentration - and that promotes fun while learning. Stepless seat height adjustment with top lift Thick seat padding: comfortable, wide seat Cover made of durable fabric Shapely and stable black base Equipped with load-dependent braked double safety castors for carpet floors. As a result, the chair only rolls under load, when it is not under load the castors brake to prevent it from rolling away unintentionally