One of the most common questions about bearings, is "What ABEC are those?" but a better question should be, what does ABEC mean? Basically ABEC is a rating system for the tolerances in a bearings. The higher the number, for example ABEC 7, the less the tolerance in the bearing. Having smaller tolerances means that your bearing will spin faster, for longer. Package include 50 Chrome Steel Balls. It is lubricated with synthetic oil.…more