This LAOWA 24mm macro "probbe" lens of Leica/Panasonic L mount is an amazing piece of engineering allowing for macro perspectives that were previously impossible due to the combined long profile and wide-angle macro design. This example is like new and includes a portable power pack for convenient use in the field. 
 
More info in this youtube clip - just skip to 1:04 for the interesting part. https://www.youtube.com/watch?v=WrzQjUQds6g
 
Loc : JN24