Accessory company Mophie has announced a new lightweight battery pack/case for the iPhone 5, dubbed the Juice Pack Air.

The Juice Pack Air features a 1700mAh battery -- 200mAh more than the Juice Pack Helium case we reviewed earlier this month

According to the company, the Juice Pack Air offers an extra eight hours of 3G and LTE, 10 hours on Wi-Fi, up to 40 hours audio playback, and up to 10 hours video playback - all packed into a light design. 

The Mophie line of cases works like this: once your iPhone reaches a low-charge, you simply flip the switch on the case to begin charging. Mophie says the new Juice Pack Air offers "up to 100 per cent extra battery". The case - and, at the same time, the phone - charge through a microUSB port.

READ: Mophie helium for iPhone 5 review

With the Air, Mophie promises: "The ideal case for the everyday 9-5er and for those whose day doesn’t always end when they leave the office."

Priced at $99 ($20 more than the Helium) the Air will ship in 7 to 10 business days, beginning 22 March, in red and white colours.

In our review of the Helium, we found it to be a great solution for adding a bit of charge to your iPhone if you don't mind the added bulk. However, with its thin design and extra battery, the Juice Pack Air might be a better solution.