Each Lucky Atom II 110mm & 100mm pro scooter wheel features Lucky's patented Rebound Technology (LRT), a combination of their own custom urethane, pouring process and curing method, which all combine to make Lucky wheels the fastest, smoothest, best-gripping wheels on earth. The Atom II features Lucky Core Lock, a unique hub design that locks the urethane to the core and prevents chunking or de-hubbing. The Lucky Atom II comes with a spoked metal core. The choice of many a pro rider and a great choice for you too. Get some!