It was basically the first fish eye made for APS-C mirrorless made by a third party, and was a stunning lens. Fully manual, no electrical contacts available, you may want to set your camera to allow to “shoot without lens”
Being that Sony E mount is the same both for aps-c and 24x36mm sensors, you can shave the hood and enjoy a very nice cropped circular fisheye on a Sony A7/A9 series model.
This lens was discontinued, and replaced with the current 11 lenses second version, a bit longer and heavier and said to be a better performer (they are so close I can’t tell the difference)
Reality says this same lens is available in many other different names, depending on the country and on the importer the list is long and complicates things. ROKINON, BOWER, WALIMEX are only some of them.