This is a Revolution Aura Bearing Set for the Associated B6.4The Aura Steel Revolution bearing is best categorized as a budget-minded performance bearing. Because it is oiled, the bearing will perform almost as well as our high-end Aura line but at half the cost. It is designed for the highly competitive racer that wants to have an edge but does so much racing that spending the money on the Aura Ceramic's isn't always practical. Just remember though, while the oil does increase performance by an immense amount over grease, it also lubricates the bearing for a much shorter period of time and will cause the bearing to fail sooner if not maintained.The bearing comes in our Revolution seal, which we innovated back in 2003, which is a rubber seal on one side and metal on the other. We are offering it this way because it is the most versatile option available. For example, if you are running in a nearly dust-free environment such as onroad or some indoor offroad / carpet tracks, you can pop off the rubber seal, leave it off, and run the metal shield facing the outside world for that maximum performance.
