... hardness, compared to 6 to 6.5 for hardened steel, and 10 for diamond. This very hard edge rarely needs ... life than the traditional steel knife, with no need for sharpeningwithin 5years or much longer.3. Stain and rust ... proof ,non-adhesion,very easy to clean.4. No chemical reaction with food ,no ... comfortable even in long time use. White lock blade,multi function pocket knife