Oh and what does that say after kat in the above picture? I just can't make it out ?
lol!! I forgot to mention you can get a gauge from McMaster, forget what the threads are but I drilled mine out and threaded m5 threads for hose fittings. The gauges are just brass fittings with a krimped copper pipe that expands/contracts under pressure. And there is plenty of brass to work with before any risk of getting to the actual expansion plate.