... for all types of excavators Single-row ball slewing ring Basic data (Q Series): The single-row four points ... contact with the circular race at four points,via which the axial force,radial force ... be born simultaneously.It may be used for slewing conveyers,welding arms and positioners,light, ... center 1250mm,Dia.of ball 40mmOEM supplier for Excavator for your reference, nice quality R260LC-7R140LC-7R210 ...