The Tilting Disc is designed to strengthen children’s proprioceptive sense and balance. The Tilting Disc consists of two hard plastic parts combined around a thick and moveable rubber connector, which gives way when children shift their center of gravity. Set includes 1 tilting disc and 1 top. Details:Yellow and green8.66" x 8.66" x 6.69"Weight Capacity: 165.38lb. For use with the Build N' Balance system (not included), or as a standalone balancing toolMade of high quality plastic