... Plastic bearing1)Material :PEEK ,POM ,UPE ,PA66 ,PI ,PTFE ,PVPF,PP ect2)Size:anyPEEK material with anti-corrosion and High temperature ... self-lubrication performance and low friction confficients .Plastic beairng made with POM is the most extensive sort of all the plastic bearings ... the inner and outer rings made with POM or PA .Cage made with PA and the balls made with glass ,stainless or ceramic , ...