Features:
Battery Extender and Case in One
Advanced Battery Technology : Highly condensed lithium polymer battery
Acoustic Sound Enhancement : redirecting sound from the bottom of the iPhone 4 to the front; resulting in a richer; fuller sound quality
4 Light LED Battery Status Indicator : displays how much time remains during the charging process
Rechargeable external battery power
Standby Time: Up to 270 hours
Talk Time: Up to 6 hours on 3G | Up to 12 hours on 2G
Internet Use: Up to 5 hours on 3G | Up to 9 hours on Wi-Fi
Audio Playback: Up to 36 hours
Video Playback: Up to 9 hours
Battery Capacity: 1500 mAh (also  has 2000 mAh  in  stock to  choose)
Dimensions: 5.07 in x 2.51 in x 0.68 in;
Weight: 2.5 oz
Color: black  blue  pink yellow purple

Package Contents Included:
Fans Battery Case
USB power cable
User Manual
Warning
1. To extend storage, please fully charge IFANS pack before first use.
2. Be cautious of excessive drops, abrasions or other impacts to IFANS power pack. Please stop using immediately if any abnormal phenomenon occurred.
3 .Do not expose IFANS to wet or damp conditions, please keep it dry.
4. Do not use near heat emitting appliances.
5. You are s ested to use included USB cable to charge IFANS pack, others might cause compatibility problem.
6. Do not attempt to replace any spare parts of IFANS pack.
7. It is normal phenomenon that IFANS pack gets a little warm when charging due to high output.
8. Never dispose of the IFANS pack in dustbin, please bring used batteries to your local battery recycling center.
9. Do not connect the IFANS to iPhone 4 if there has been occasions of prolonged non use.
One year limited warranty.
Specifications & User Manual