Ricta Wheel Dynamics' 52mm Chrome Core Black Gold 99a Wheels offer a uniquely speedy and low rolling resistance due to 20 years of perfected cored wheel tech. Ricta's top-notch urethane gives the Cores extra speed while providing shape-consistency, even after hard landings, for speedy rollaways. Attributes: Family- Chrome Core; Road Surface- 18; Size- 52mm; Wheel Hardness- 99a; Width- 31. Ricta 52mm Chrome Black Gold