Ceramic Hybrid 6004-2RS C3 Chrome Steel and Ceramic Balls Ball Bearing 20mmx 42mmx 12mm 6004-2RS Hybrid ceramic chrome steel sealed bearing with ZrO2 Ceramic Balls Electric motor quality, Bearing 6004-2RS is a popular size that could be used in many application that uses this size 20mm x 42mm x 12mm, each 6004-2RS bearing is closed with 2 Rubber Seals, double sealed and one seal from each side to protect the bearing from dust or any possible contamination, also bearing is pre-lubricated with grease, Bearings 6004-2RS has industrial packaging.