The base is what separates a leaning stool that works from one you stop using. At 16.1 in in diameter, this one is wide enough to stay planted when you shift your weight sideways, which happens constantly when you are half-standing rather than sitting. A narrow base on a tall stool creates exactly the instability that makes people abandon the idea after a week. The seat rises from 23.6 in to 33.3 in off the floor, covering a conventional desk at the bottom of the range and a standing desk at the top. It measures 16.1 in deep by 15 in wide and is padded with foam under a Pu surface, which wipes clean and does not hold warmth the way fabric does over a long session. The size is deliberately compact, since a perch works by keeping your hips open and some weight on your feet rather than letting you settle in. Construction combines polypropylene and steel, carrying a static load of 265 lb, and the stool weighs 20.9 lb assembled. That mass matters on a stool with a round base.