GCE Argon Single Stage 0-32L/min flow gauge regulator
You may recognise these regulators from GCE because GCE used to manufacture the regulators for MUrex / Esab before Esab decided to part company and buy from China.
These simple single stage regulators are for use with argon / mix shielding gases. Typically it is these simple single stage regulators which are provided "free" with welding machines as they are generally the lowest priced regulators and simply have a normal pressure gauge but the gauge is calibrated in flow - litres / minute instead of outlet pressure, how this is made possible is by the regulator outlet having an orifice restrictor which causes pack pressure, the higher the back pressure the higher the flow through the orifice restrictor and the higher the indicated flow on the pressure gauge.
These regulators show an approximate flow when the gas is flowing however be aware that when the trigger is released and the gas has stopped these regulators will indicate a higher flow!