The Switch Pitch (also called the Switchball) is an innovative color changing toy invented by Chuck Hoberman (inventor of the Hoberman Sphere). It is literally two balls in one. When you toss it in the air with a little spin, centripetal force (sometimes called centrifugal force) causes the ball to flip inside out and change color. The Diameter of each ball is approximately 4 inches. We are out of Blue / Purple. The only color available at this time is Green / Orange.