Nineballs have been a long-time favorite of skaters from all walks of life. From cruising kids to freeriding chargers. All these wheels provide good roll speed. 74mm Diameter, 78A Durometer, 50mm Contact Patch. Nineball Urethane, Better Roll Speed, Sharp Lip Shape for Extra Grip, Offset Core, Natural Finish Provides Extra Grip, Larger Size Rolls Over Debris and Imperfections, Larger Size Helps Hold Speed Longer.