FR155-2RS Flanged Sealed Ball Bearing, Bearing is a popular size that could be used in many application that uses this size 5/32" x 5/16" x 9/64" inch, each FR155-2RS bearings is closed with 2 Rubber Seals, bearing is 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.