Datel Duo Controller (Nunchuk) for Nintendo Wii. Features 3 axis motion-sensing technology with an analog stick to assist in character movement. Ideal for multi-feature games that require ‘nunchuck.’ The Duo Controller is a secondary controller that adds even more innovation to the next generation of gaming. It doesn't need its own power, it plugs into the Wiimote remote controller when it's in use. So there's no need to worry about charging or replacing batteries.