Gaiam Balance Disc Wobble Cushion Stability Core Trainer for Home or Office Desk Chair & Kids Alternative Classroom Sensory Wiggle Seat Turn almost any chair or seat into an active one by placing the disc on top to add instability and strengthen your core. This posture-improving inflatable 16" Balance Disc will engage your abs and core muscles while you sit. Great for a meditation seat or wherever you need a little extra cushion. By controlling the firmness of the cushion, you can adapt it to your fitness needs and comfort-ability. Can also be used for strengthening exercises in or out of your chair Product Features ACTIVE SEATING: Place the disc on top of almost any chair or seat to add instability to strengthen your core while improving posture and sitting comfortably - great for office desk chairs VERSATILE CUSHION: Use balance disc with a variety of strength and balance exercises, in or out of a chair, to increase core strength and balance MEDITATION CUSHION: Works great as meditation seat or wherever you need a little extra cushion - also effective as a 'chill chair' for young children and active kids ALTERNATIVE SEAT FOR ACTIVE KIDS: Great for classroom aged children at home or in the classroom as an outlet for hyper or ADHD kids allowing them to release excess energy while staying engaged and focused longer DIMENSIONS / INFO: Measures 16 inch diameter / Arrives partially inflated and ready for use / Includes Inflation Needle to inflate or deflate for cushion preference / No Pump Included