With our Pneumatic Stool with back, adjusting your height (within a range of 19" - 26") is as simple as pressing a lever, and you can do it while you're sitting. The seat is a 17” diameter, base is 21.5" diameter. Available with or without a back, in your choice of vinyl and color to match your table. Natursoft colors: Marie's Beige, Latte, Black, Mystic Blue, Amethyst, Teal, Vanilla Crème, Burgundy, Hunter. Other colors available at additional cost. Comes with foot ring, but can be removed.