... .ever sharp,durable,eco-friendly 4.factory price,fast delivery 4inch hotselling high quality wear resistant zirconia black ceramic knife ... Materials: Using high-tech Zirconia crafted, high-density, high hardness, never wear, hardness (HRA87) is next to diamond, and abrasion performance ... of its extremely high density and bright the knife is not easy to breed bacteria, cutting fish, fruits, vegetables ...