The Spinner & 4 Way Joystick upgrade adds two more controls to your control panel: a dedicated 4 Way Joystick and a Spinner. You will receive an additional sub-list on our 5000 Game List specifically for spinner games. Dedicated 4 Way Joystick:This is for games such as Pac Man, Donkey Kong, etc. that only use 4 way movement, as well as games like Discs of Tron which require both a spinner and joystick to use. This joystick is for Player 1 only.Spinner:This is for games such as Arkanoid, Discs of Tron, Kick, etc. that originally had a spinner dial to play. The spinner is for Player 1 only and will only work in the Spinner Game List.This upgrade is considered a "functional" upgrade however it is not mandatory as the Trackball that comes included with the Signature Series machines will work in place of a spinner for games such as Tempest, Arkanoid, etc.This upgrade is an additional $250 CAD.