Of course the Photonic Instrument has to be able to be turned on and off. So the simplest and easiest method is to build a hand wheel operated switch that squeaks when turned. At least no one will accidentally turn the instrument off with a casual swipe of the paw. The issue of the squeaking can be solved by greasing the shaft. This is the inside of the switch, where a smaller blue industrial limit switch can be seen at one end. The M12 nut is fixed, so as the M12 studding is rotated, it moves against the roller lever attached to the limit switch. The industrial dia.12 bearing on the outside of the box keeps the shaft running freely, albeit with an annoying squeak.