This looked to be just what I wanted, to replace my existing Nexus 7 charger that was showing signs of failure. It came in a plain white thin cardboard box, with not product description at all, which in itself is a bit suspicious. It's a stylish device and looked well made but I very soon realised there would be problems. The label on the underside of the device proclaimed that is is 800 microamps, whereas the Nexus 7 requires a 2 Amp charger.
I've tested it out and it managed to reduce my battery from 59% power to 54% when left on charge overnight. That was with the Nexus turned off. But for the power rating label I'd day it was faulty. This is the second time I've bought a charger where the description claimed in could charge a tablet (the other was for an Archos 101 G9) but the product is simmply a mobile phone charger. In the first case the vendor, did offer a refund and went to the trouble of checking with his supplier. This is advertised for the Nexus 7 and it is not fit for purpose. Indeed the description almost certainly infringes the Sale of Good Act, and the Advertising Authority Code.
For those who want a replacement smartphone charger with a micro usb fitting this actually works well - it will charge my wife's Samsung Galaxy Ace and even my Samsung Galaxy S2 - it just won't charge a tablet.
Please, vendors, check to see that the product can actually do what you claim it can do. As this order was fulfilled by Amazon they should certainly have known better.