Deep groove ball bearings are the most widely used bearing type. It has deep, uninterrupted raceway grooves. These raceway grooves have the close osculation with the balls, enabling the bearings to accomodate radical and axial loads in both directions.
In addition to open type bearings, these bearings often have steel shields or rubber seals installed to one or both sides and are pre-lubricated with grease. Also, snap rings are sometimes used on the periphery. As to cages, pressed steel ones are the most common ones. For big deep groove ball bearings, machined brass cages are used. Machined cages are also used for high speed applications.

Maximum type ball bearings
These bearings are single-row deep groove ball bearings with a filling slot on both the inner and outer rings. They feature an enhanced radial load rating as they can contain more balls of larger diameter.
Not suitable for applications that involve axial loading or high-speed rotation.
When the bearing is installed, the filling slot on the fixed bearing ring should be in a no-load area.