Amazon is offering the uNu Power DX External Protective Battery Case for iPhone 5S / iPhone 5 for $50 shipped. Today’s deal is available in both the black and red version, and while the white one will run you $60 on Amazon right now, you can grab it for $50 on Groupon. This is $40 under the regular price and within $5 of the best price we’ve ever seen (holiday 2013) on these MFI Apple Certified battery cases. This is matching the lowest price we’ve seen on the red and white models.

It features a 2300mAh built-in battery (equals an additional 10 hours talk time), and a bonus screen protector, and lip to keep your phone safe as well as charged. Wirecutter thinks it’s one of the best available iPhone 5 battery cases on the planet, in fact the second best behind only the Lenmar Meridian — mostly due to it being a slightly slower charge and usually more expensive.

Quite frankly, it comes down to price: We consistently find the Meridian for $5-$10 cheaper than the uNu. But if that changes, and you don’t mind the slightly slower charging speed of the uNu, you’ll do just fine picking the DX up instead,” said Wirecutter. With today’s deal, both cases are about the same price, with the uNu as much as $10 less in red and white.

The uNu Power DX External Protective Battery Case for iPhone 5S / iPhone 5 has received a 4.1/5 star rating among over 550 Amazon customers.

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