This isn't actually a lens, but an adapter to fit microscope lenses into an SLR-body.
I bought it together with a microscope lens, and to me it's essentially just an extreme macro lens. The lens itself can be changed, and there's a lot of options when it comes to microscope lenses ... and they are surprisingly inexpensive, so there's an option to experiment. The one I have is 4X, but you can get some that are 100X - hardly useful on a camera, but other less dramatic options are avaiable too.
It's a fun toy and it can take some really close closeups, but its use is also limited for the same reason. You simply get so close that it's almost difficult to control. The depth of field is millimeters (if it's even that much), and shooting hand held requires a ton of light.
The viewfinder image can be difficult to see because it's very dark, but as I said: it's a fun toy, which may have some serious uses in the hands of the right person.
I paid 60.- USD for the lens and adapter, and 15.- to have it shipped, so it wasn't crazy expensive.
Girls just wanna have fun!
