The Powerslide Spinner Wheels in these smaller sizes use  reinforced Universal Cores combined with a special urethane compound designed to withstand the demands of urban freestyle and slalom skating.
 
The Spinner Wheels can do intentional slides well, and can take on stairs, jumps, etc... They are fast and durable at 88A hardness. The profile (footprint) is labeled as 'race' by Powerslide, but we believe this to be a catalog error, as they look to have more of a full profile for better grip, control, and stability.