HVAC/R supply house. High side gauge. 0-500 PSI 5 PSI increments 1/8 NPT port. Some are liquid others are non. I have a non liquid gauge and I can also readjust the needle to read zero. I have used one for years. I have a 0-1500 PSI liquid filled for all work above 500 PSI. Pretty much accurate against older 1.25 inch face, minis and micros. Checks out with other test gauges known to be true.
just my 2 cents.