The Audio-Technica AT8471 is a simple microphone mount/clip, for use with a variety of Audio Technica microphones. Specifically, I've used the AT8471 with the AE2500 dual element microphone. This is a really sturdy microphone stand and will be suitable for use with a variety of other microphones of a similar size as well. The nice thing about the AT8471 is that you can adjust the size of the clip, making it useful for all different sorts of microphones. It's really a sturdy clip and will undoubtedly hold your microphone in place where you want it whether for use in the studio or on the stage.
I don't know exactly which Audio Technica microphones the AT8471 comes with other than the AE2500 which I've used it for. It's fully adjustable in terms of size, so I wouldn't be surprised if this was the clip being used for most of their microphones. It can indeed be purchased separately from any microphone, so if it will fit your microphone it should work with mics of all brands. However, it can only be adjusted to be so wide and I don't think it would fit something like a Shure SM57, just microphones with a relatively skinny width. It's definitely a good clip to have around studios as it will still fit a variety of microphones and it's always good to have a few extras around. I don't know what it costs to buy this individually but being what it is I'd be surprised if it was much at all. I wouldn't say it's the most versatile mic clip, but definitely does seem like it would have a pretty good reach considering the adjustable size as that's not something most mic clips have. It's a sturdy clip overall, so definitely check it out if you have an Audio Technica mic that needs it or otherwise.