As a complete and self-contained N2O-O2 delivery system, the portable can be moved from one operatory to another. The unit is comprised of a flowmeter, an "E" yoke manifold with pressure regulators and gauges, a mobile stand, a scavenging system, corrugated tubing and a reservoir bag. These, plus gas cylinders and the operatory vacuum system, are all of the components needed to administer nitrous oxide-oxygen analgesia.

In the portable system two or four compressed-gas cylinders are attached to "E" yokes, which are connected to pressure regulators. The regulators provide nitrous oxide and oxygen at the proper pressure to the flowmeter.

Mobility is the major advantage of the portable unit. It is usually the system of choice in offices where space limitations will not accommodate a central storage room or when economic constraints are an influencing factor. Also, the portable system is most likely the answer when frequency of N2O-O2 use is low.