Nunchuck

Nunchucks are used in Wii Sports for Boxing & is used for some games outside of it

Controls
A Nunchuck has these controls C, Z, & an analog stick.

Trivia

 * The Nunchuck is the only attachable accessory that can't be built in.
 * In Wii Sports it's only used in Boxing it makes sence by you boxing with 2 arms.
 * It's not optional for any sport in Wii Sports.
 * It's the only attached accessory used in Wii Sports however it's optional to use a Motion Plus for any game.
 * It's mainly used for fighting games like the Wii U Pro Controller.