I think that's what they are promising. At that low price the optics are probably dodgy so images may not be usable. Unfortunately you get what you pay for with lenses. That said it's not a big outlay if you want to try it.
I tried out the Raynox 2.2x Converter on my G1 with the 45-200. The resulting image quality (at 880mm!) was worse than by using only the tele and cropping the pic to the same size in postproduction.
So I continue using the Converter only for HD-videos (Panasonic TM 700), where it produces excellent results.