Those are Vibrachecks. I don't believe that they are available any more. They are much like the unit that b0w bender built.I don't know where they got them, but Lancaster Archery Supply has a couple of Genesis bows in their showroom with similar devices on them. They are there for folks to try out releases before purchase.
I used to have one and hated it. It didn't give the feel of a regular shot because it threw off the balance of the bow. I couldn't get a vibracheck shot to translate to a regular shot. For me a blank bale in the basement works much better.