Pair 10" Passive drivers - Very unusual & unique Take a look!

Description

Have for no reserve auction a pair of 10" passive radiators. I have never quite seen anything like them, but are well constructed and so unique?
They consist of dual metal baskets back to back with rubber surrounds on each side. A center styrofoam mass literally floats between the baskets. The rubber surrounds are on the soft side.
The outside diameter measure differently on both sides, as though the smaller diameter would slip inside the larger cutout to the large diameter side.
Even is you have information about them, I am curious...
hanks for looking