... second to diamond Ceramic Knife – High Density ZirconiaModel: 3", 4", 5.5", 6.5", ceramic knife eriesBlade Material: zirconium dioxide (ZrO2; also ... . Never rusts and will not taint food with metallic taste.Factory Advantages: ISO Certificate, LFGB,SGS,EU Test Reports provided, ... us directly, it will shorten our handling time and provide better services to you. Thank you. 6.5 inch ceramic knifes