The O-16 NSK is a type of single direction thrust ball bearing, also known as a ball thrust bearing or axial deep groove ball bearing. It comprises three main components: a shaft ring, a housing ring, and a ball and cage assembly. These bearings have an open design and are well-suited for high rotational speeds due to the presence of rolling balls.

Single direction thrust ball bearings are designed to withstand axial loads in only one direction, allowing the shaft to be axially secured in that direction. However, they must not be subjected to radial loads.

Since thrust ball bearings are separable, their components can be installed individually. During assembly, take care not to confuse the shaft ring with the housing ring. The shaft ring is mounted on the shaft and rotates with it, while the housing ring has a slightly larger bore to allow the shaft to pass through with a small clearance.