499502-2RS Full Ceramic Sealed Bearing ZrO2 5/8" x 1-3/8" x 7/16"499502 2RS Full Ceramic Bearing Zirconia 5 8" ID x 1 3 8" OD x 7 16" Wide This 499502 2RS full ceramic ball bearing is sealed with PTFE covers and built entirely from tough zirconia ceramic. With a 5 8" inner diameter and precision engineered components, its built for high temp, non magnetic, and corrosion sensitive environments where metal bearings just wont cut it. Made entirely from Zirconia (ZrO) ceramic Sealed with white PTFE covers on both sides