The Rs series flow meters are instantaneous variable area flow meters suitable for the dosing of medical gases, in this case oxygen and medical air. They can be made with compensated or uncompensated pressure, and in both single and two-meter execution to allow double and independent delivery using a single power source. The Rs series flow meters have a needle valve with a knob that ensures immediate recognition of the feed gas through color coding.

The body is made of chrome-plated brass with metal fittings. The measuring unit is made of polycarbonate, a material with high mechanical resistance which therefore makes this device particularly suitable for the heaviest uses. They are also available in a variety of calibration pressure solutions, various scale, normal or extended scale options (L version) to allow for better graduation reading.