Super Hard Inox - Special, chrome-nickel, stainless steel, slats, work hardened for high resistance, with shiny surface having a roughness of Ra < 0.3 microns. - Chrome-nickel, austenitic stainless steel pins (18% Chrome - 8% Nickel), work hardened for high resistance. Super-G Hard Inox - Special, chrome-nickel, stainless steel slats, work hardened for high resistance, with a rubber insert. - Chrome-nickel, austenitic stainless steel pins and guide shoes (18% Chrome - 8% Nickel), work hardened for high resistance.