Manufacturer designation:

688.H.ZZW6

Designation due to standards:

638/8-2Z 

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.
W6 is a special dimension of the bearing width.