Stainless steel blades and Carbon steel blades.Very precisely grinded edges according blades numbersby the very well skilled engineers, and all blades aremanufactured by the full automatic computerized machineswith the strict quality control according production batches.Sterilization by Gamma-Rays.Specification of manufacture:Size: #10, #11, #12, #13, #14, #15, #18, #19, #20, #21, #22, #23, #24, #25. Packing specification:Individually aluminum foil packaged.100pcs/box. 5,000pcs/Carton box.