3 years & up. Transform a standard school chair into a Wobble Chair with specially designed Wiggle Wobble Feet, enabling kids to have an outlet for excess energy while working. Continuous movement results in alleviating anxiety, hyperactivity and boredom, increasing focus. Kids' concentration grows as they rock back, forth and all around because the continuous movement increases blood flow to the brain enabling greater attentiveness. Simple installation - the Wiggle Wobble Feet snap right on to a standard round school chair glide, turning the seat into a Wobble Chair. No tools required!  The 2.6"h and 3.8" diameter feet can be used on tile, wood and carpeted floors.