Formed foam seat with flattened seat edges and a high backrest featuring custom upholstery design, durable and long-lasting. The backrest provides optimal support and stability due to its three-dimensional shape. The high foam density prevents sagging and ensures long-lasting seating comfort even during periods exceeding 8 hours. The height-adjustable backrest allows for individual adjustment to the lumbar region. The beveled edge at the front of the seat prevents blood clots in the thighs. The seat and back move in sync with each other. The chair follows the movements of the sitter when opened. The movement can be locked at any angle. The counter-pressure of the backrest can be infinitely adjusted using a hand wheel. The back is continuously supported, relieving the abdominal area, which helps prevent tension and promotes an upright sitting position. This achieves a homogeneous pressure distribution in the vertebrae. With individually adjustable pressure, the chair can be tailored to different body weights, enabling fatigue-free work for over 8 hours. High stability.