This 20mm straight style MAX Inside Ring Polisher is used on ring sizes 11+.   Consists of 3000 grit MX abrasive throughout which provides a brilliant high-shine. Requires no compounds so jewelry is easier to clean and your hands stay clean too. MAX Inside Ring Polishers screw onto a steel Motor Adapter (sold separately) to fit polishing motors with 1/2″ or 5/8″ straight shafts (right-hand side only). You only need one adapter because MAX Inside Ring Polishers have internal threads to easily screw on and off the adapter for a secure hold. And that means they always run true.