This heavy duty office chair tilt control mechanism is designed to support up to 500LBs. It features a 4mm thick tilt plate and a single lever for gas lift cylinder height activation and tilt locking. The unit includes a hand wheel for adjusting tilt tension and allows for a 3 to 15 degree seat rock angle. The mounting hole center distance measures 6 inches wide by 10.2 inches long. This mechanism accepts standard 28mm diameter tapered gas lift cylinders. Please measure your existing bolt holes and mechanism size before purchasing to ensure proper fitment.