RLS8ZZ Sealed Ball Bearing 1" x 2 1/4" x 5/8" inch One Bearing RLS8ZZ Bearing is double Shielded, radial and deep groove ball bearing,RLS8ZZ bearing is made of Chrome Steel with chrome steel balls and steel cage,bearing is closed with Metal Shields to protect the bearing from dust or any possible contamination,RLS8ZZ bearing is Shielded and self lubricated,the quality is set to EMQ (electric motor quality) to ensure high speed,RLS8ZZ bearing is lubricated with grease.