... ball with LED lights and counter PMMA Plastic case, Rubber Anti-slip strap, Metal ball core Wrist ball,power ball,roller ball,gym ball, promotion ball,gyro ball ... Uint size:dia appro×6.9mmDimension:43×39×34.5Unit weight:230g 1.power ball,roller ball2.with ... speed counter3.with LED lights4.durable plastic with steel axle5 ...