flow meter is for a finer or more accurate adjustment. also, it takes a certain IPM of shielding gas to ionize a certain amount of voltage . furthermore, you can actually blow away the molten material if the flow is to high. I prefer and have flow meters on all my welders over regulators as I do particular welding on different materials. you should stop buy your local welding supply house and get or buy a GOOD weld directory for the consumables that are available. good luck