This all new 82a SSF PRO formula found in 59mm G-Slides, which is only possible through the magic of urethane formulation. On hot days, or under heavier skaters, I expect the blue and yellow will leave colorful 'thane lines. At 82a, this new formula will reduce the chunking which is common in our 75a or 80a wheels. You could describe the 59mm 82a G-Slides as an upgraded RoughRider that resists chunking and slides much easier.