CenturionPro TableTop Tumbler O RingThe Tumbler O Ring is a key mechanism in our successful CenturionPro Tabletop series. Its Polyurethane ring attaches to the tumbler wheel adding durability and strength. In addition, its powerful structure provides a maximum amount of friction. Therefore, allowing each tumbler to consistently turn with ease at just the right speed. The O Ring is works with the electropolished steel tumbler and also the Quantanium coated tumblers. It as a versatile and