Question 1

How long is this antenna, it doesn't say in the specifications?

Accepted Answer

12 inches even. It's in front of me right now. However, it didn't seem to improve my range and speed.

Question 2

how does it attach to the computer?

Accepted Answer

IT screws on to your wireless card, base or router connectors.  It must have a male SMA screw-on connector to connect to. The SMA connector is pretty standard, I have one of these connected to TPlink wen 4800 PCI-E card, a rosewill dual base antenna, and router.    You can see if you have this connector by looking at the device's specs

Questions & Answers