Extra battery for VP-2

Specifications:

• Rechargeable Lithium-Ion Battery for VP-2 Model
• One Single Battery Duration: Up to 3.5 hours   Volume： 6400 mAh
• One Double Battery Duration: Up to 6 hours    Volume：10400 mAh

The single/double Battery is a rechargeable Lithium-Ion battery for the VP-2 model. It provides portability for your active lifestyle. When you're away from a power source, this battery will keep your concentrator running so that you can stay active longer. A single battery will give you up to 3.5 hours of battery life, or a double battery to provide 6 hours of use time.