OEM Honda 13012-ZOT-801 piston rings are .020" (.50mm) over standard size and can be used with oversized pistons, OR as file-fit rings for standard pistons. Pack includes 2 oil rails and an expander ring, a scraper ring with a lower chamfer on the outside diameter and a chrome-faced compression ring with upper chamfer on the inside diameter.
The chamfers on these rings, especially the one on the compression ring, make these rings superior to anything else available for these engines. This compression chamfer is very important as it utilizes the combustion pressure to force the compression ring into the cylinder wall giving the best possible seal. This is a necessity to get higher performance out of long-lasting chrome-faced rings. "Gas ported" pistons seek to achieve the same goal. These are not legal for AKRA Box Stock Class.