ZZ structure

ZZ usually means a metal shield structure. It is suitable when some dust protection is needed and lower rotation resistance is preferred.

RS structure

RS refers to a rubber seal structure. It usually provides stronger protection and is suitable for environments with more dust, moisture or contamination. Speed and resistance requirements should still be checked.

Open structure

Open bearings do not have shields or seals. They usually have lower resistance and are easier to lubricate, but require a cleaner working environment.

How to choose

  • Choose RS when dust or moisture protection is more important.
  • Choose ZZ when light dust protection and lower resistance are both needed.
  • Choose open structure when low resistance or lubrication maintenance is preferred.
For website wording, use “available with ZZ, RS or open options” unless stock status has been confirmed.