Smooth - Smooth wheels come with a shiny coating on the riding surface that feels grippy at first, but wears away quickly.
Wheel Profile
Wide - More traction and stability at high speed so you'll be less likely to slip out of your line.
Wheel Tech
Rapido Formula - A perfect balance of speed and smooth control. Ricta's Rapido formula offers longer slides when you want it, and heightened control when you need it. Flat-spot resistance gives you a faster, smoother, and longer ride.
Durometer
99a - Offers more grip than harder wheels and more slide than softer wheels. Great for slick surfaces when you want more control.