The EasyPulse External Rechargeable Ion Battery attaches to the EasyPulse Concentrator and provides approximately 3 additional hours of use (settings at 2 lpm). It will double the battery life of the unit if used in conjunction with the internal battery, giving you more freedom and time to do the things you love the most.
  Proper Use: In order to prolong the life of the battery, it is best to charge the battery frequently rather than waiting until the battery is fully discharged.
  Storage: When storing for long periods of time without use (> 1 month) be sure to charge the battery to around 50% charge level to prolong life of battery.
  Approximate Hours:
    - Setting 1: 4.5 hrs.
    - Setting 2: 3.2 hrs.
    - Setting 3: 2.5 hrs.
    - Setting 4: 1.8 hrs.
    - Setting 5: 1.5 hrs.
  Warranty: 180 day