Depending on their series and size, SKF self-aligning ball bearings are fitted with one of the cages shown in table as below:

Cage type	One-piece,  ball centred	Two-piece,  ball centred	One-piece snap-  type, ball centred	One-piece,  ball centred	Two-piece,  ball centred
Material	Stamped  steel	Stamped  steel	PA66, glass fibre  reinforced	Machined  brass	Machined  brass
Suffix	–	–	TN9	M  (no designation suffix  when d ≥ 150 mm)	M  (no designation suffix  when d ≥ 150 mm)

When used at high temperatures, some lubricants can have a detrimental effect on polyamide cages.