You need to order a "tail" (the wires with a 3 or 4 pin connector attached). Notice that the wires are hooked up to a connector on the fan that can be easily removed and replaced. The tail costs about $1. I did the same thing when I ordered my first Panaflo a few weeks ago. Great fans once you get them hooked up. On my second order, I bought both 3 & 4 pin models. For some reason, the 3 pins ones didn't work, so at least this time I was prepared with a backup plan!