Certain arcade joysticks included a restrictor plate that limited the movement from 8 way (which includes diagonal operation) to 4 way (with no diagonal movement).  In other words playing 4 way games on an 8 way joystick can lead to unresponsive gameplay that feels sloppy.  

    To solve this you can buy two seperate joysticks with each of these hardware restrictions or just use the Servostik to switch between modes on the fly.  That's right, with the Servostik 4 way joystick gaming is now automatic!  These amazing "Servostik" joysticks will automatically switch from 8 way operation to 4 way operation based on your game selection.  Play games with authentic-feeling, tight controls and the setup is automatic!  See a full list of 4 way joystick games.

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