6301RS Sealed Ball Bearing 12mm x 37mm x 12mm 6301RS Sealed Ball Bearing is radial and deep groove ball bearing,6301RS bearing is made of Chrome Steel with chrome steel balls and steel cage,bearing is closed with rubber seals to protect the bearing from dust or any possible contamination,6301RS bearing is sealed and self lubricated,the quality is set to EMQ (electric motor quality) to ensure high speed,6301RS bearing is lubricated with grease.