That's a bionator I think.
I got one made probably about 12 years ago. It always looked like an interesting appliance to wear.
I have mentioned it a few times in past posts. Once it is in, there is no jaw movement at all. If I open my mouth it stays in position on my bottom teeth and the top plate and wire are clearly visible of course. As I close down on it, everything fits into place, just like a normal hawley retainer but the jaws are held in place.
Most people would think you were wearing top and bottom retainers with wires and you can speak quite well. You can drink but you can't eat of course.