Edges are measured by different companies in different ways, some include teeth, some do not.
ON3P uses a 2.5mm by 2.5mm edge bar, not including teeth. Its ground a bit when we structure and finish the skis, but its the thickest we can get our hands on, and its Rockwell 48. If you are wondering difference between different types, higher the number the harder the material. Some may say that softer is better for impact vs harder, but so far as I know, nobody has done a published study on ski edges and rails to date.