Multiplex Delivery System (MDS) The MDS allows the investigator to use up to six stations simultaneously using only one vaporizer and ensures proper fresh gas flow rate to each station used. This affords maximum safety for the animal subjects. The MDS is available in 2,3,4,5 and 6 flowmeter configurations and includes a pressure relief valve. The pressure relief valve will vent pure O2 (not anesthetic gas) into the environment in the event the O2 flowmeter on the anesthesia machine is turned on without any individual flowmeters being turned- preventing vaporizer damage. This pressure relief valve can easily be installed on any anesthesia system.