I got to play with one of these for a day or so running it through its paces before my wife confiscated it. May have to get another.

Mini Review
This is a 3200mAh rechargeable battery about 3.75" long by .75" round. it has a microusb/charger port and a full size USB to connect to your charging cable. Ive used it to recharge my phone and tablets and it charged my tablet while it was on at 50% brightness at 1894mw... which is pretty good considering the tablets normal charger only kicks it up to 2309mw. Even at 100% brightness on the tablets screen the battery still powered the tablet and continued to charge the tablets battery at 1302mw. So in a pinch this will recharge your phone or tablet for some extra run time on the go. As a plus, it also doubles as an LED flashlight.

Here is the link on Amazon , free shipping for prime users
http://www.amazon.com/gp/product/B00PMTFDOM
Sold by AAT LLC and fulfilled by Amazon .

Its on sale now for $18.99 (down from $39) but use the coupon codePXTBLSCPfor $3 off to bring it down to $15.99 after coupon.