S6200 Open Ball Bearing Premium ABEC-5 Quality with Si3N4 Ceramic Balls (Silicon Nitride) 10mm x 30mm x 9mm S6200 open stainless steel ball bearing, radial and deep groove ball bearing,S6200 bearing is made of Stainless Steel with Ceramic Balls (Si3N4) and Nylon Cage,the quality is set to EMQ (Premium ABEC-5 quality) to ensure high speed,inner diameter is 10mm, outer diameter is 30mm and width is 9mm.