A tiny bluetooth antenna, but works to perfection. I have a bluetooth mouse that I wanted to use on my new laptop (no Bluetooth integrated), but without a 5cm cube that exceeds the rating. It is now done, this mini-antenna exceeds a little less than one cm, and as it is semicircular she will not take anywhere and does not catch the son. I put my PC leaving it without fear of breaking everything.
Recognized by Vista, I just had to plug it in and the rest is done alone. A very small discrete green LED flashes on the inside to say she is on, and my mouse was running perfectly.
In short: I am very happy, especially for the price!