Slicks precision skate bearings are high-performance skateboard bearings built for speed. The bearings come pre-lubricated with the highest quality lube to reduce friction and increased speed. The low contact bearing shields also work to reduce friction while protecting the balls and spacer from dirt and debris, drastically increasing the lifespan of the bearings. The balls are made with heat treated stainless steel making them extra hard for a decreased contact patch and more speed. With an ABEC 9 tolerance, these bearings are no joke, especially with their affordable price!