These durable, comfortable stools hold up to 300 lbs. and offer simple pneumatic height adjustments. The height range is measured from the top of the seat with no compression. Premium Swivel stools, with or without back rest are offered in all our TerraTouch and UltraTouch II colors. The Back Rest Stool is FDA Approved. Premium Swivel Stool: 18"-23"; 21"-28"