Teledyne Hastings Instruments” HFM-I-400Series linear massflowmeter is designed for measuring medium-to-high gas flows. The linearityof the laminar flow element allows for accurate measurements onthe same instrument when changing between gases such as Nitrogen,Hydrogen, Ethylene, Propane, and Methane. Six gases are standard, and up to eight gases can becustomized. Measurement is available on boththe digital and analog output.