The Koyo 6004ZZ Single Row Ball Bearing is built from durable steel and designed for reliable performance in moderate radial and low axial load applications. It features a 20 mm (0.7874 in) round bore, with a riveted steel cage and dual shields for added protection. With C0 internal clearance and a single-row design, this bearing ensures smooth operation and stability, making it a dependable choice for light to medium-duty machinery.