... row, metal body 2.good balance 3.lifespan 6-8times of press steel 4.soft, mid-hard and hard bond separatly Usages ... grinding, leveling, shaping and polishing stone surface, corners,edges and angles.Other sizes and types as below:- Size(inch)3, 4, 5, 6, ... : customize color availableMore pictues of double row cup wheel as below:- diamond grinding cup wheel for marble and granite surface,corners,deges ...