It’s an inspection tool used to check against its allowed tolerances via a go/no-go test. The check involves the electrodes having to pass one test (go) and fail the other (no-go).
This is available in two different sizes (2.5 mm and 4.0 mm) to choose from.
It comes with an analog display and toggle switches.
The PACT-OTS-GAUGE is used to set the spacing between the electrodes fitted inside the oil test set cell.