Unique child friendly seats offer the advantages of a traditional wiggle seat, but with a lot more fun! Allows children to quietly move while working, enabling them to stay on task and be more productive. Flexible nubs on one side and smaller bumps on the other give a choice for just the right amount of tactile stimulation. Ergonomic base causes the body to stabilize itself, improving posture. Portable alternative to balance balls with the same benefits. Easy-inflation pump is included and firmness can be customized to contour exactly to each child's needs. Average 13" diameter is a great fit for a kid's seating while being large enough to grow as the child does. Effective on chairs, benches, or directly on floors.