Thats a two motor wheel spinner. The shiny drum in the middle runs on the wheel and there is a motor on each side of it, the two motor units will spin big heavy wheels. I think that unit is actually made by Hunter. I have a single motor with a different looking motor and base unit, with a lift up lid that houses the weights and the balance unit and at least two of the wheel adapters. The single motor unit struggles somewhat and I've used it only on smaller wheels such as 195/70/75-14's. As old as mine are, the rubber on the wheel adapters is still in good condition. I use it occasionally, and have always been extremely careful to make sure the wheel adapters were securely locked in the rims, to the point that I pull real hard on them, and I also carefully lock and verify by pulling, each of the four locks on the red balance mechanism. There is an art to using them, I can make it work, but am not as good as some of the old timers I recall seeing use these things 35 or 40 years ago.
The balance mechanism was just overhauled by Hunter when I bought mine from a family friend who owned a Hertz franchise. He was closing down the shop as he was transitioning from cars he owned to cars he leased that stayed under warranty, and he was getting rid of his rental trucks, the prime reason for the shop. I bought the balancer and a old sulfur dioxide refrigerant compressor that I added a 1/4 horse motor to and casters and make a excellent vacuum pump out of (still have it too).
Charles