Roller ball bearings (yoke type track roller bearings based on ball bearings) are designed to operate on all types of tracks and can be used in cam transmission devices, conveyor systems, etc. The outer running surface is equipped with a spherical shape as standard. Double row roller ball bearings with cylindrical surfaces (with straight busbars) and outer race running surfaces can also be provided. The roller ball bearings provided by SKF are pre filled with grease and sealed, and are ready to install bearings.