These brand new, professional grade bearings by Bronson Speed Co are pre-lubricated for a smooth, fast ride. They come in the standard size (608 with an 8mm core, 22mm outer diameter, and 7mm width) and provide the best for performance and durability. Deep Groove Raceways – balls roll deep in raceway channels – reduces side impact damage & breakage High Speed Ceramic Oil – Nano-ceramic compounds for wear protection – moisture, rust, corrosion resistant Straight Edge Frictionless Shields – pop off resistant – holds oil in, dirt and moisture out – easy to clean