... grease Our company mainly dealing in deep groove ball bearing,such as,60series,62,63,68,69series and ... so on. The best material for bearing is high carbon chromium bearing steel,which has hardness,strong rolling fatigue ... shield sing or both sides(z,z);with non-contact seal on single single or both sides (L, ... 2L ),and with contact seal on single side or both sides (RS,2RS). ...