I'm pretty sure these will not work with a modern router, at least the one that I have installed in my iMac G3 700, can't connect to my router. It can't even see the network, because my router doesn't support the early 802.11 standard that the Airport card uses. I have had to use an ethernet cable, every time I wanted to use it online. It's also dangerous to use the original Apple Airport hardware (including the original grey, UFO base station). The encryption it uses (WEP, only) is too weak, and can be hacked in less than 5 minutes. I can understand wanting one to make your iMac complete, which is the reason why I went to the trouble of tracking one down, but using it to get online could be problematic. You're a lot better off using ethernet, or an external wifi dongle that supports a later standard.