self-aligning bearings for high and complex loads.
One row bearings have one row of barrels, spherical outer ball-track and one inner ball-track.
Double row bearings have two rows of barrels, spherical outer ball-track and two inner ball tracks.
Angular position of the barrels to the bearing axle makes possible both major axial and radial load transfers in two directions
They are usually manufactured with cylindrical bore for direct on-shaft mountings or with taper bore with taper 1:12 on diameter for assemblies on adapter sleeves. The 240 and 241 series are produced with taper bore with taper 1:30 on diameter (K30) and mounted on adapter sleeves of the same taper.

Bearings with lubricating groove and bores in the outer ring are designated W33 or S

Designation E after the bearing marking means modified internal design which improves carrying and rotation parameters.

Common versions are those with greater clearance: C3 and C4

Widely used are steel and brass cages, but for certain usages polyamide ones are much better