Change the orbit and the ball will run around it continuously.
One steel ball is the simplest and four are the hardest.
Playing helps with one's concentration, coordination and reaction speed.
Adults and children both like to play it, relieve pressure and relax mood.
WARNING：This toy is not suitable for children under three years old because of small parts.Color: blue,pink,greenMaterial:plasticLength: 9cm (3.54in)Width: 5cm (1.97in)Height: 1cm (0.39in)