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Anker® Astro Slim3 6000mAh Ultra-Slim External Battery Pack with Built-in Micro USB Cable and 2 Ports Portable Charger Power Bank for USB Devices (Black)

by Anker
4.4 out of 5 stars  See all reviews (317 customer reviews) More about this product

Price: £49.99
Sale: £19.99 & FREE Delivery in the UK. Details
You Save: £30.00 (60%)
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In stock.
Sold by AnkerDirect and Fulfilled by Amazon. Gift-wrap available.
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Technical Details

  • The Anker® Advantage: Join the 6 million+ powered by Amazon's #1 charging brand.
  • Fast Charging: One USB port charges the iPhone 5s at full speed and one built-in Micro USB connector charges Android devices up to 1 amp. The Slim3 recharges in 5-6 hours via the included Micro USB cable and 1 amp adapter (not included).
  • Uber-High Capacity: Add almost three charges to an iPhone 5s, one and a half charges to a Galaxy S5, multiple charges to most other phones or one charge to an iPad mini.
  • Ultra Slim: Compact design (0.47in) and flat, rubber surface make it easy to hold and stack your device on top while charging. "Hideaway" Micro USB charging connector for Android reduces cable clutter.
  • What You Get: Astro® Slim3 External Battery, Micro USB cable, welcome guide, our fan-favorite 18-month warranty and friendly customer service.

Special Offers and Product Promotions

Frequently Bought Together

Anker® Astro Slim3 6000mAh Ultra-Slim External Battery Pack with Built-in Micro USB Cable and 2 Ports Portable Charger Power Bank for USB Devices (Black) + 30 PIN Dock Connector to Micro USB Adapter For Apple iPhone 4 4S 3GS iPod iPad 2
Price For Both: £21.98

These items are dispatched from and sold by different sellers.

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Product details

  • Product Dimensions: 13.4 x 7 x 1.2 cm ; 231 g
  • Boxed-product Weight: 259 g
  • Delivery Destinations: Visit the Delivery Destinations Help page to see where this item can be delivered.
    Find out more about our Delivery Rates and Returns Policy
  • Item model number: AK-79AN7909-B2A
  • Date first available at Amazon.co.uk: 18 April 2013
  • Average Customer Review: 4.4 out of 5 stars  See all reviews (317 customer reviews)
  • Amazon Bestsellers Rank:

Product Description

ANKER: Amazon's #1 Charging Brand

• The highest average review rating of any charging brand.
• One in three chargers sold on Amazon is from us.
• Join the 6 million+ satisfied customers powered by Anker.

Astro Slim3 External Battery
Mobile power that stacks up - literally.

Fast Charging
Charge an iPhone at full speed via the USB port and Android devices at speeds of up to 1 amp through the built-in Micro USB charging cable.

Built-in Micro USB
For Android and other Micro USB devices, leave your cords at home and charge up with the Slim3's handy "hideaway" connector.

Uber-High Capacity
Packed with power, charge an iPhone 5s three times, a large capacity phone like the Galaxy S5 over one and a half times or an iPad mini once.

Slim & Stackable
Specially designed to suit a 4.7in smartphone. Just stack your device on top and enjoy uninterrupted use while charging.

World Famous Warranty
At Anker, we believe in our products. That's why we back them all with an 18-month warranty and provide friendly, easy-to-reach support.

For Optimal Use:
• Use the included cable, your original cable or a third-party certified one (such as MFi).
• Compatible with Apple and Android smartphones, tablets (including the Nexus 7) and other USB-charged devices except for the iPod nano, iPod Classic, HP TouchPad, LG G2, Asus tablets and some GPS and Bluetooth devices. The built-in Micro USB connector may not work with thicker bumpers or cases.

Customer Questions & Answers

Customer Reviews

Most Helpful Customer Reviews
27 of 31 people found the following review helpful
5.0 out of 5 stars Compact, Portable and Long Life Battery.... 11 Sep 2013
By Dario
Size Name:6000mAh
I was supplied a sample for test and evaluation, and I promised that my review is fair and honest.

The product is aesthetically very nice and well done. It is accurate in all its details, and it is pleasant to the touch. It is very thin and it has the dimensions of a Samsung Galaxy S4. It has similar height, width and thickness. It is just a little bit heavier nut the weight is very light and everything is in favor of portability. You can easily carry with you in your pocket like a mobile phone without any problem.

The very simple package includes: the battery Slim3 of course, a little manual, a cable usb-microusb (pretty short, about 30cm) for charging and an 30pin adapter for iphone 3gs/4/4s (it only works for charging and not to synchronize). It has also a built-in and not removable micro usb cable that is very useful if you have a device that need a microUSB connector to be charged, a little less in other case, such as an iphone, because then you will need to connect an adapter. There is also a second USB port where you can connect, for example, or a second device to charge it simultaneously, or to connect the cable for iphone 5, for those who haven't an adapter or simply to connect a longer cable. Missing a bag to carry, not the battery because it is pocket size, but to bring the usb cable and the adapter.

It is extremely easy to use. You connect the built-in cable or a usb cable to the secondary port to a device, and without pressing any button, it starts the recharge. At the end of the recharge, the battery is automatically turns it off so to not consume and discharge the battery. It is equipped with 4 LEDs that indicate the state of charging of the battery while it is charging a device and when it is recharging itself.
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3 of 3 people found the following review helpful
4.0 out of 5 stars it really does hold its juice. 16 Jan 2014
By RnB
Size Name:6000mAh
Pros; Good looking piece of kit, well made, very portable, super fast charge with on board cable, good delivery (traceable) and well packaged, gives my Xperia S three full charges.
Cons; it takes a long long time to fully charge (Zzzzzzz), it does get hot when charging phone (with on board able), no case.
Summary-I do like it, to be honest I can't do without it. However, due to the Cons it gets 4 stars
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20 of 23 people found the following review helpful
Size Name:6000mAh|Verified Purchase
This product is noticeably more expensive than the slim2; however, it appears to be the exact same product with slightly different labeling. The previous one is labeled as having a capacity of 4500mAh (unknown voltage), while the new one is labeled as having a capacity of 6000mAh at 3.7V. Some basic maths and knowledge of physics tells you that the two capacities are the same. Power*time=voltage*current*time

Misleading labeling does not end here. The product is specific to out-put 1A, which is a lot. However, this is at 1.5V, which is 300mA at 5V. 5V is the normal USB voltage.

I don't want to bother sending this back and buying the slim2 which is 7GBP cheaper. I do, however, feel properly ripped off.
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15 of 18 people found the following review helpful
5.0 out of 5 stars Nicely designed product 20 Aug 2012
By mwarner
Size Name:3200mAh White|Verified Purchase
I contemplated a number of products before finally deciding on the 3200mAh Anker. I intend this to provide my phone with extra charge whilst out walking & using the phone as a GPS - I tend to find that after 5-6 hours of this kind of heavy use my phone runs out of juice!

My requirements were:

1. Able to provide roughly one full charge of my Samsung Galaxy Note (2500mAh battery)
2. To be slim enough to not really notice you are carrying it in a pocket (thickness is more important than width and height here). I compared it to an iPhone 4S and it is slightly shorter, but pretty much the same width and depth.

I also liked the following about this item:

1. It had a built-in light, which I will actually find quite useful
2. It had a built-in Micro USB cable, making it more compact than having to carry around a separate cable.
3. The price was very reasonable

Once in hand, I was impressed with it's build quality and weight and, comparing it to my workmate's 5000mAh I was pleased I ordered the lower capacity version - mostly due to the excellent form factor.

Today I decided to perform a test to see how efficient battery to battery power transfer is. I ran my phone down until it asked for power & charged it until the (fully charged) extended battery ran out of juice.

The recharge took 3 hours and took the phone from 16% to 87% battery before running out of power. The phone was on during this time - the previous 3 hours had used 16% battery, so I assumed that the battery usage over the charge period would be the same.
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5.0 out of 5 stars A Life Saviour for Your Phone 22 Oct 2014
By Austen
Size Name:6000mAh|Verified Purchase
Excellent and well designed. It is about the same size as a normal smart phone.

It charges/recharges at about 0.5% per minute; e.g. it increases the charge in my Samsung Core phone by 50% in 90-minutes.

It will charge a normal smart phone about twice so that should be enough for travelling and if you get bored at an airport and use your phone heavily to watch videos or listen to music. I bought this because my phone was flat when I arrived at an airport and could not call my wife, nor the office, nor the airport car park company to come and collect me. So this 'power bank' will save me in future.

The cable/mini connector tucks nicely away for travelling so it will not get lost. The case is matt black.

It is supplied with a separate cable to connect to a USB charger but a charger is NOT supplied. Apparently you can plug into your PC USB to charge up this battery but a separate small 5v USB charger is far more convenient both when travelling and at home/office.

The price of £20 is about average for 6000mAh power banks which are heavily discounted nowadays owing t0 the intense competition.
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Most Recent Customer Reviews
3.0 out of 5 stars Three Stars
Built in wire won't charge most of the time, external one does.
Published 3 days ago by Gediminas Stankevicius
4.0 out of 5 stars but I could be wrong) I'd defiantly recommend getting one
I bought two of these, one for me and one for a friend. Mine has held up perfectly and have had no issues. Read more
Published 9 days ago by linmcg
5.0 out of 5 stars Slim, comfortable in a pocket and charges well
I trust Anker, I have bought many of there products with no problems. However, if I had a problem, I would also trust Anker's customer services to deal with it (as they appear to... Read more
Published 15 days ago by fredjk351
3.0 out of 5 stars solid performance. bigger than most phones.
worked well at first, then started to lose capacity. now, the plug is not holding, and replacing the port on the phone made no improvement.
Published 16 days ago by Robert Orlando
2.0 out of 5 stars It was ok for the first 2-3 months and when ...
It was ok for the first 2-3 months and when i stored it for a few months - it does not even charge anymore - no lights, nothing
Published 20 days ago by Albert
4.0 out of 5 stars Great size and weight, good product!
Great product, I have used it many times and it has provided me with extra battery life, up to 2.5/3 charges. Read more
Published 21 days ago by aboooday
4.0 out of 5 stars OK, but built-in micro usb cable not very durable.
Update 14/11/14 - So, Anker saw my 3-star review below, and sent me an email asking if they could replace my unit. Superb customer service. Read more
Published 1 month ago by Mr. N. Webber
5.0 out of 5 stars Three Stars
I love the design but the built-in usb is not stable
any way it can be used.
-------- --------
have to change my comment to 5 stars. Read more
Published 1 month ago by moca
1.0 out of 5 stars Bought one.. It wouldn't charge anything through the ...
Bought one.. It wouldn't charge anything through the attached plug, only through external socket and extra lead. Thought it must be faulty so got it replaced. Read more
Published 1 month ago by David
2.0 out of 5 stars One charge only
You can get about one full charge from empty or 14% HTC One from a single battery charge. It makes your phone really hot and causes lag and performance issues. Read more
Published 1 month ago by Zubba
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