Single row crossed cylindrical roller slewing bearings are simple in design, consisting of a one-piece inner and outer ring and cylindrical rollers separated by polyamide spacers and generally protected by integral seals.They can accommodate heavy radial loads and medium axial loads as well as tilting moments. These slewing bearings are intended for bearing arrangement swhere stiffness is important or zero operational clearance or preload as well as constant resistance to rotation are required. Single row crossed cylindrical roller slewing bearings require tighter specifications for the flatness and stiffness of the support surface than single row four-point contact ball slewing bearings.