We're grouping R-2 and SG-2 in the same section for now. They're basically the same steel. SG-2 is a powdered stainless steel that is well known for excellent wear resistance and is considered a great steel for high end, high quality kitchen knives. – Made up of Carbon: 1.25 – 1.45%, Vanadium: 1.80 – 2.20%, Chromium: 14.00 – 16.00%, Molybdenum: 2.30 – 3.30%, Manganese: .40%, Phosphorus: .03%, Sulfur: .03%, Silicon: .50% This is Takefu Specialty Steel’s PM (powdered metallurgy) steel. It has very high edge retention like ZDP-189, but has less wear resistance making it much easier to sharpen. Shun and Fallkniven are two of the more popular makers using this steel in their production lines. This steel is also called R-2 steel.