The amazing new Dragon Formula (DF) Urethane used to create these wheels is another innovation from the folks at Powell Peralta. DF-93A Dragons will not only roll over rough terrain, but also grip and slide like 99A and 101A wheels do, so that you can do all your normal tricks and more on the greater range of skate terrains made skateable by its softer 93A hardness.
Put simply: Dragons slide on both rough and smooth terrains, and also grip when you need it.