Our Mass flow meters for gas use Laminar Flow Element technology. This is a subset of differential pressure flow meters. User selecs gas Rapid response NIST traceable All common non-aggressive gases such is air, nitrogen, argon, helium, hydrogen, natural gas and carbon dioxide. Digital indication with either a voltage or a current transmitter Type 4 construction (weather proof) Built-in alarm switches Able to install in any orientation Intrinsic safety optional