They probably work just fine no idea. Bought a tank of refrigerant and these came with it.
Dont know anything about them. This item is in the category "Business & Industrial\HVAC & Refrigeration\HVAC & Refrigeration Tools\HVAC & Refrigeration: Gauges & Probes".
The seller is "grubbs38" and is located in this country: US. This item can be shipped to United States.