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All the parts to upgrade your own Atari/Commodore/SMS joystick to USB. Can be put inside the controller or built real Atari/Commodore/SMS ports onto your computer. Kit includes board, USB cable, and requires soldering.
Any controller that uses the Atari digital joystick standard will work with these products. Included are the Atari 130/400/800/2600, Commodore 64, Sega Master System, and others. Analog controllers like the paddles are not supported.