Ben's Outlet - Leopard Ultra-Thin Protective Battery Case for the iPhone 4 & 4s w/ USB Cable – Available in Black & Wh

Features Include:
Power and charge your iPhone 4 or 4s
Extends battery life by up to 4.5 hours of talk
Can charge your iPhone and battery pack at the same time using the USB power (included)
1900 mAh battery capacity
5V 500mA input and output
Around 3 hours charge time
Small enough to keep connected to your iPhone
Dimensions: 2.5 x 5 x 0.7”
Weight: 2.4 oz.