Manufacturer designation:

SFR4ZZ
S.F-R4 ZZ

Designation due to standards:

WOBF89ZZX ST 

Design:

The ball bearing consists of two rings (internal and external) and rolling elements (balls), connected with a cage - separator.

Features:

Made of high-carbon chrome bearing steel, characterized by high wear resistance and rolling fatigue strength.
Covered with a layer of stainless steel for working in aggressive environments and at high humidity.
Closed on both sides with seals of the ZZ type.