The Wiggle Wobble Chair Feet transform a standard school chair into a Wobble Chair. Enabling kids to have an outlet for excess energy while working, alleviating anxiety, hyperactivity and boredom. Greater focus leads to higher grades and improved academic performance.Installation is simple as each "foot" snaps right onto the standard round school chair glide (measuring between 1.125 and 1.25" in diameter) turning the seat into a Wobble Chair -No tools required! The 2.6" H and 3.8" diameter Wiggle Wobble Chair Feet can be used on tile, wood and carpeted floors. Special Shipping Information: This item ships separately from other items in your order. This item cannot ship to a P.O. Box. This item may be subject to additional processing days. ITEM IS NOT ELIGIBLE FOR EXPEDITED SHIPPING You may initiate a return for unused items within 30 days, if the items are in original packaging with all original materials included with the shipment.