https://tsi.com/products/flow-meters,-flow-sensors,-and-flow-analyzers/flow-meters/4000-series-analog-and-digital-flow-meters/mass-flow-meter-41403
Mass Flow Meter 41403 - TSI
The TSI Nitrous Oxide Mass Flow Meter 41403 (LCD, 0.01-20 L/min / N2O, Air, O2, N2/ 1/4" tube) can be used for a multitude of gas flow measurement applications.