Prong’s PWR promises to provide your phone with power, preventing all problems. It’s a slim-ish case with a built-in battery along with a pair of flip-out power prongs that can be thrust directly into a wall outlet.
The Prong PWR, which is the sequel to the charge-only PocketPlug, keeps the previous case’s flip-out prongs, letting you plug the case or the iPhone and case straight into the wall to charge it, and adds a 1,500mAh capacity battery.
This battery is detachable, so you could – if one is made available – carry a spare. The case also ships with a USB cable so you can charge your iPhone the old fashioned way, but the real reason it’s there is for sync.
The only time I ever carry a backup battery case is when I travel (or when I’m testing one I guess). And traveling is also the only time I drop an iPhone charger in my bag. So having both in one package is a great idea, although for everyday use I’d fid it a little bulky. Finally, I like that the price is similar to that of a battery case, at $80 (you can pre-order to get one for $65).
Interested? It comes in black and white, and you can pre-order.
Source: Prong