No. 91893 Abrasive Compound No. 91893 abrasive compound replaces #533 abrasive in all Champion spark plug cleaner units. Cleaners formerly using the #533 abrasive will require two bags of 91893 to fully charge the unit. The chart below should be followed when replacing abrasive: 1. Use two bags of 91893 abrasive to fully charge Champion 2400, 800H, 800E and 700 cleaners. 2. Use one bag of 91893 to fully charge the CT475AV cleaner/tester. Each bag of abrasive contains one #622 nozzle tip. Operators using two bags of abrasive should remember to remove and save the extra nozzle tip.