Your new comfortable office chair - the Topstar Sitness 55 Read on to discover all the interesting product details for the Topstar Sitness 55 office chair! Healthy seated posture with a patented seat joint Equipped with the BODY-BALANCE-TEC®, the model offers a particularly comfortable seat. Its integrated seat joint provides three-dimensional mobility (BODY-BALANCE-TEC®) and thus supports your pelvis and relieves your back. Durability of the Topstar Sitness 55 office chair In a timeless and elegant black, the Topstar Sitness 55 office chair makes a good impression in any office. It is also composed of 75% pure wool and 25% polyamide. The base is made from steel. The durability of the material is clear from the 100,000 abrasion cycles. For office use, the figure should not be less than 20,000.