Features: Classic rail twister: It uses the power of magnetism to mesmerizingly move the wheel along the rails with the quick flick of the wrist, all while producing a fascinating light show. Up and over, back and forth, it is hours of magical fun. Develop motor skill while having fun: Gyro wheel will trigger teens’ curiosity to learn more about physics, magnetism, and gravity, and the movement of the wrists also helps to improve their motor skills, help them stay focused, and providing stress relief. Easy to play with: Just a flick of the wrist is enough to get the fun started. Specifications: Size (approx. ): Rail twirler: 26 x 5 x 3.5 cm/ 10.2 x 1.97 x 1.38 inches Wheel: 5 x 5.5 x 2.5 cm/ 1.97 x 2.17 x 0.98 inches Color: as shown Package includes: 6 x Magic tail twirler (the wheel contains batteries) Warm note: Suitable for people aged over 12 years old.