It does what it says, most of the time correctly. Occasionally, if you don't pay attention and shake the laptop abruptly, it disconnects and you have to unplug and plug it back in, but overall it's a good purchase.

I bought it to connect my new MacBook to my home screen. Everything is fine.
Edit: I removed one star because after a few weeks of use, it seems to not always make good contact. Sometimes, when the laptop moves a little, the second screen disconnects and I have to shake it a bit to make contact again.

Edit 7 months later: The slightest movement of the laptop causes it to lose contact and sometimes it takes quite a bit of "jiggling" to get it to connect again. I remove another star.