A 62303 ZZ/2RS open 17x47x19mm thickened chrome steel bearing is a type of deep groove ball bearing. It is designed to support radial and axial loads and is commonly used in a wide range of applications, including automotive, industrial, and agricultural machinery.

The 62303 ZZ/2RS bearing has an outer diameter of 17 millimeters, an inner diameter of 47 millimeters, and a width of 19 millimeters. It is made of thickened chrome steel, which provides strength and durability. The "ZZ" in the bearing's name indicates that it has two metal shields on either side of the bearing to protect it from dust and other contaminants, while the "2RS" indicates that it has two rubber seals on either side to keep lubrication in and contaminants out. The "open" design means that the bearing does not have a cover or enclosure.

Deep groove ball bearings are characterized by their deep, continuous grooves, which allow them to accommodate high radial and axial loads. They are simple in design and relatively inexpensive, making them a popular choice for many applications.