Full&love Rock Hopper Pogo Exercise Balance Ball Board for Kids Adults with a Pump (red) Ball Diameter: 6.27" / 21 cm;Board Diameter: 15.16" / 38.5 cm;Board Thickness: 0.67" / 1.7 cm The board is made of high strength wearproof plastic, the ball is made of the high quality PVC Does not occupy a space, easy to burn calories, have healthy slim figure only 10 minutes every day The board and ball are removable.Designed according to the human body engineering. Several kinds of collocation methods, fully motivate your sports cells, up and down steps at the same time can turn right or left, adjust the pelvis, shrink the lower abdomen, optimize your waist, hip curve