The pack's display usually holds information, such as remaining time, or power, depending on the game being played. There is a black button on the front that players can press to light up the display, or that is sometimes used to join some games called "black button games", where knowing how many players are participating is important. There is also a round part on the front that receives a member's login button, or login tab, which is used to attribute statistics from certain games to a member account, so that a member can see how they compare to other players over an accumulated number of games.