For an economical traditional spherical bearing, QA1's COM-T Series is the perfect choice. Each bearing is made from chromoly steel with a self-lubricating PTFE liner. Ball 52100 Bearing Steel. Heat Treated. Hard Chrome Plated. Precision Ground. Liner PTFE. Self-Lubricating. Race Chromoly Steel. Heat Treated. Protective Coated for Corrosion Resistance.