7 x 17 x 5 Stainless Steel Sealed Ball Bearing Nylon Cage 7 x 17 x 5 Stainless Steel, Sealed, radial and deep groove ball bearing, bearing is made of Stainless Steel and Nylon cage, bearing is closed with rubber seals to protect the bearing from dust or any possible contamination, bearing is sealed and self lubricated, bearing is lubricated with Oil.