S6801 Open, radial, deep groove ball bearing,S6801 bearing is made of Stainless Steel with Ceramic Balls (Si3N4) and Nylon cage,the S6801 inner diameter is 12mm, the S6801 outer diameter is 21mm and the S6801 width is 5mm,the quality is set to EMQ (Premium ABEC-5 quality) to ensure high speeds.