Our (EOS) Portable Emergency Oxygen Systems allow you to have a minimum of 10 minutes of oxygen per person. This is the needed amount of oxygen time for emergency descents starting at 25,000 ft. in the event of a cabin de-pressurization as defined by the FAA.
To operate, simply don the masks and turn on the main cylinder valve. Oxygen will flow only if a mask is connected. A positive flow indicator on each mask shows oxygen is being delivered.