Wobble Stool is the perfect balance chair for active sitting. This ergonomic office stool creates a healthier sitting environment by moving with you throughout the day - safely rock, swivel, tilt, lean and burn calories while sitting. Originally designed to be the best standing desk stool, Wobble Stool extends tall enough to let you perch near standing height, making the move between sitting and standing fast and effortless.- BALANCE STOOL: Wobble Stool"™s patented base lets you sit still or gently rock, tip, twist, lean and swivel 360. Move more and sit actively with this unique office balance stool.- STANDING DESK STOOL: the best perching stool for standing desks. The height adjustable Wobble Stool extends to 33.5 in., letting you rest from standing without going all the way down to a normal height chair. Wobble Stool is easy to sit on and quick to get up from.- COMFORTABLE OFFICE STOOL: NEW triangle, saddle seat is engineered for better comfort! Wobble Stool has a 3"� thick seat cushion made of premium molded foam that waterfalls over the edgeless seat frame and is covered with a vinyl for a cool, comfortable seat.- DURABLE ROUNDED BASE makes it easy to rock, swivel and move around while sitting. You don''t need to be in constant motion or balance because the special base design allows you to sit comfortably in a stationary (non-balancing) position. - TALL ADJUSTABLE HEIGHT WOBBLE STOOL (23.5-33.5 in.): lets you sit higher and stand up more frequently during the workday. - NON-SKID BASE securely grips most floor surfaces including carpet, wood, tile. PRODUCT SPECS •  HEIGHT RANGE: Adjustable ~23-33"�•  SEAT DIAMETER: ~13"�, Triangle Saddle Shape•  SEAT MATERIAL: Premium, 3"�+ thick custom-molded high-density foam. Vinyl cover•  PRODUCT WEIGHT: ~20lbs•  ASSEMBLY: Simple 4-step assembly | No Tools Required | No Screws | Takes 1 minute or less.All measurements are approximate.