EW-4 Oxygen System features: 

• Provides 18 minutes of life-saving oxygen (@ 6 lpm).
• Safe and easy to use.  Ready in seconds to deliver life-saving oxygen.
• Cylinder measures 9" tall, weighs 2 lbs.
• Capacity: 113 liters, 4 cu.ft., delivered empty
• Portable, convenient,lightweight, no tools required 
• Meets all FDA requirements for portable emergency oxygen. 
• Training program explains the proper use and care of the oxygen system and the administering of CPR .
• Available in 4, 6, 9 and 15 CF models.