SR6-2RS Sealed Ball Bearing ABEC-5 Quality with Ceramic Balls (Silicon Nitride) 3/8" x 7/8" x 9/32" Inch SR6-2RS Bearing is double sealed, radial and deep groove ball bearing,SR6-2RS bearing is made of Stainless Steel with Ceramic Balls and Stainless steel cage, SR6-2RS is ABEC-5,bearing is closed with rubber seals to protect the bearing from dust or any possible contamination,SR6-2RS bearing is sealed and self lubricated,SR6-2RS bearing is lubricated with grease.