Review on 🌡️ Elitech VG-760 Digital Vacuum Gauge Micron Meter for HVAC Refrigerant Leakage Test - 1/4'' SAE by Alex Gilbert

I first used it on my pressure gauge kit. Reached 400 microns prematurely. Solid Evidence. I'll be using it in a project this weekend. I have emailed Elitech at the customer support address. No response after 4 days. Questions: Does the display show "_ _ _ _ _ _" until a vacuum greater than 19,000 microns is achieved? (I confirmed this when I tested it. Although their photos show "19000" when not plugged in); When I turned on the device, two codes were displayed. The manual does not contain code descriptors. So I wasn't sure if I should use a pressure gauge. Couldn't wait due to upcoming project.