I just bought one of these last week. Found it at an airport 'gadget' shop here in Pittsburgh.
http://www.naztech.com/naztech-cat-power-banks/285-naztech-product-bp15000-universal-power-bank.htmlIt's pricey at $149, but the super high capacity, all metal case, and the digital display that reads out in voltage made it a buy decision for me. So far, I'm very happy with this decision. The only negative thing I can say so far is, why no 6V setting?
I'm up to 48 hours continuous run-time and have two of four bars still lit. Tascam DR2D running with the backlight on, internal mics, high gain...using tips that are included in the battery package and the 5V power jack on the Tascam and the USB port on the battery. I think I'm pretty safe suspending this run-time test and concluding that this will safely run my recorder all weekend for a festival.
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Details and Specs
Naztech PB15000 Universal Power Bank
High Capacity Back-Up Battery
The Naztech PB15000 Universal Power Bank is the ultimate backup power source for all your mobile devices. With included adapter tips for smartphones, MP3 players, tablets, laptops and netbooks, this is the only backup battery you will ever need. Within its sleek and portable design, the PB15000 packs a colossal amount of power that translates into hours of extra usage. Perfect for road warriors and busy professionals, the PB15000 allows you to spend less time charging your device and more time using it.
USB Port Output: 5V, 200mA (MAX)
Size: 13mm L x 21mm W x 175mm H
Output: 9V, 12V, 16V, 18V, 19V, 20V, 21V
Output Power: 60W (MAX)
Input: DC 18V-2000mA
Cycle Times: More than 500 times
Charge Protection: Short Circuit / Overcharge
Capacity: 15000mAh/55.5Wh
Battery: Li-Polymer
Weight: 400g