This is the world’s thinnest iPhone 4 case with battery charger that nearly doubles the life of your battery. Say goodbye to chunky and clumpy additions to your iPhone that can make it almost impossible for it to fit in your back pocket. With the Power Sping’s sleek form fitting design we are extremely confident you will love this product.
Mili Power Spring 4 HI-C23 External Battery Features:
Special deisgn, is compatible with iPhone 4
Very thin and slim, it is the thinnest external battery for iPhone in the world