I like Norax belts very much as well as Trizact "Gator" belts. I have seen conversion charts for both brands of belt. The conversion chart rightly says for "new" belts. I have found that with Norax belts I can refine a 220 grit bevel with a slightly used X100 belt which the chart shows as about 150 grit equivalent but it usually smooth's out my grind and I follow it with X65 and then X45 before heat treat. The Gator belts last longer and cut a little bit more aggressively but both brands are better for finishing than for establishing a bevel in my opinion. This has been my experience so far with dozens of each belt. I have been taking out small scratches from bevels with a 400 grit Hermes cork belt and am starting to use cork belts on all my knives. They are inexpensive and come in 220, 400, 600, 800, and 1000. I may have an addiction problem with buying a lot of new belts though, Larry