Excerpt: I had been using a Tunderbolt to Ethernet adapter for the internet connection on my Macbook Air. But I bought a new monitor, and the Thunderbolt connection had to go for the monitor. I bought this adapter and plugged it in. Works great.
Unbelievable: you need to use a non Apple driver to make it work!
Ivan Z, Apple Store
11 January 2013
Summary: I use the adapter with a MB Air 4,1 (11" Mid11) - Mountain Lion 10.8.2 I tried to use it with a Cisco Hub and it did not work. I thought it was the cable, or the hub, then I found this on Apple discussions forums that this is a common problem and you need a an external driver to fix the problem. I downloaded the driver from driversworld.us, I installed it and now it works. Still, I found appalling that an official driver product requires a non Apple driver to work.
Summary: The ethernet port on my iMac (~2 years old) got fried in a lightening storm. Getting this was a lot cheaper than getting it fixed. Thge documentation said it only worked for a MacAir, but I decided to try it anyway. It didn't work at first, but so...