When used with specially designed games, Wii MotionPlus tracks players' movements in finer detail and with greater accuracy than ever before, building upon the innovative wireless function of the motion-sensing Wii Remote controller. Even the slightest twist of the wrist or turn of the body is replicated exactly on the TV screen, allowing users to become even more immersed in Wii gameplay. Wii MotionPlus is designed for easy attachment to the Wii Remote controller (sold separately).