I thought I should post a few pics of the Kensington Battery Pack and Charger for iPhone because as of today I have purchased four of these units (not all for myself). At 20quid these are a bargain as you get a USB charger with UK and EU socket, a iPhone charge/sync cable, a USB cable and of course a 1800mAh backup battery. I have found it will charge an iPhone 3Gs one and a half times.

One great feature is that it allows 'through charge' which means you could use it as an intermediate device when using green energy (solar, wind) or if your USB output doesn't quite have enough amps to charge the iPhone directly.

The important specs:

• 1800mAh Lithium-Ion Polymer.
• Input: 5VDC (Mini USB) - 1.00A Max.
• Output: 5VDC (USB) -- 1.50A Max.
• Weight 0.22 lbs.
• Battery Pack dimensions 4.0"L X 0.37"H X 2.2"W

(Solar charger not included)

Update: @curtwalker found the Kensington battery for £14.99 http://amzn.to/btd4RG it doesn't have iPhone cable but has country adapters and a pouch!

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