Steven did a nice job for his airsoft friends in the Phillippines. “I just used some cardboard backing to mount the circuit boards and made cutouts to the underlying foam padding to make space for the battery box, relay, extra buzzer, and a separate 9V battery to power the buzzer.” When the case is closed, the foam padding of the cover presses down enough on the red button such that when you open the case, the timer automatically starts and he made use of the “low power” feature to avoid battery drain when the case is closed.