Sick of mashing your fingers on the buttons during your favourite shmup? Getting wrist ache from the constant tapping? Then invest in a quality autofire board!
These boards appear to be clones of the autofire PCB offered by MAK Japan (or possibly from teh source where MAK get there ones?), and offer variable autofire for up to three buttons for both player one and player two.
The board connects at the JAMMA edge between the harness and your gameboard, and the autofire rate (and on/off) is controlled by DIP switches.