Don't be fooled by the size of the Arctic Power Bank 4000, it actually packs a great deal of juice.

Design

This nimble affair may be just the battery pack you've been looking for. It's light, weighing just 107g, has skinnier but similar dimensions to that of the iPhone 5 & 5s, but somehow manages to secure a respectable 4,000mAh of capacity. A rugged rubber back and brushed aluminium top is available in silver, pink, blue and black. And this whole package is priced at a mere £14.90 within the UK on Amazon and $19.95 within the USA on Amazon.

Charging & Features

So 4000mAh from our testing was enough capacity to fully charge a drained iPhone 5/5s/5c twice. And because the Power Bank 4000 has a USB 2.0 5v/2000mA female output, it will charge tablets, including an iPad (iPad Air to just over 30%), but can only charge one device at a time. The speed of charge appears to be the same as that from charging directly from a wall plug. Something we couldn't test was the low leakage Mosfet which guarantees 3 years of standby time. We've had the Power Bank 4000 in the studio for around five months and, without using it for three months, it kept a full charge. The front of the battery pack has a USB 2.0 output, a micro USB input for charging the battery pack and an LED charge indicator.

How It Stacks Up

This amount of storage, coupled with a very slim design, creates a highly pocket and bag friendly device, it even comes with a travel bag and charging cables. All this is definitely an incentive to carry it as a competent full backup solution for smartphones and compact mobile devices, instead of simply a top-up sort of battery pack. The Arctic Power Bank 4000 is comparable in size to the TYLT Zumo and the Mophie Juice Pack Powerstation Mini, but near doubles the capacity of the Mophie and near triples the offering from TYLT.

Overall

Summing up the Arctic Power Bank 4000; it's possibly the cheapest portable backup battery we've ever reviewed, but that definitely doesn't make it cheap in quality or presentation. It's exceptionally durable with its aluminium top and compact design, and surprisingly it packs a large amount of juice from which you can truly quench your device's battery thirst.