As I recall, it used a wire brushes only, ideal for the rubber balls of the era. In production for many years up until Brunswick replaced it with the Lustre King I believe. The Lustre King differed by using a dense cloth buffing wheel and utilized a compound block for a polishing agent. Also an excellent machine if properly maintained.
Thanks for sharing this
We used to joke that repeated use of these wire-brush machines gradually made your bowling ball smaller. That’s how we kidded a guy the first time he put the ball through the baby split (3-10) without hitting either pin. Of course, that kind of thing happens regularly today.