A Micro 4/3 lens that is allegedly very similar to the Panasonic Leica 15mm f1.7 but with a different coating. Bought it to try shooting wider field of views but I much prefer shooting narrower. It is pretty much brand new - I've only put it on my camera a couple of times. The firmware version is 1.1 so continuous auto-focus on Olympus bodies will work. Can also confirm this is the case as I shoot on an Olympus body.