The innovative Kore Design Wobble Chair with it's gently-rounded bottom encourages active sitting and allows one's knees, hips and back to find comfortable and ever-changing positions; continuous movement increases Secondary Focus. Great for older children and young teens, the seating height can be easily adjusted with the 360° Actuator Ring to grow with your child. Seat height can be fine-tuned between 16.5" and 24". Suggested for ages 9-14; Grade 4-9; child height 53"-70". • Manufactured with Antimicrobial Protection against the spread of common bacteria; FDA approved and successfully tested to reduce up to 99.9% of common bacteria including E. coli, listeria and S. aureus. • Provides an outlet for children with high energy or sensory seating needs like ADHD or Autism. • Homework, reading, drawing, eating or board games are no longer sedentary activities. • A patented anti-tip safety ring on the gently-rounded base prevents tip-overs and falls. • Third-party tested and passes government regulations for children's safety. • Assembles easily in 5 easy steps and is made of durable, recyclable plastic and steel piston. • Reduced pressure in piston allows a gentle bouncing "pogo" effect. • Satisfaction guaranteed with a lifetime warranty. • Plastic parts made in USA.