The SuperSonic ABEC 9 Bearings feature precision honed races and a nylon ball retainer, which makes it convenient for servicing.  A Sonic synthetic gel and polymer cage dampen noise vibration, while the deep grove raceways assist with lateral stability.  In addition, these Sonic bearings have an inner step that makes it difficult for dirt and debris to reach the ball bearings.  As a result, they will run smoother, faster, and longer.