Kataoka Mfg knife sharpener water sharpener 3 made in Japan Brieto Body: ABS resin (rubber paint) Whetstone: Alumina ceramics Made in Japan Material  Raw materials: Body / ABS resin (rubber painted), main body heat resistant temperature: 80 degrees Whetstone / alumina ceramics (rough grind: PWA # 100, medium grind: PWA # 180, finish grinding: PWA # 400) Sharpness rises For double-edged knives