Classic Urethane by OJ Wheels. 97a means they're fast and great for parks but will still roll over rough streets and cracks a bit smoother than a real hard street wheel would. Killer slide.
Wheel Diameter (Millimeters): 61
Wheel Durometer/Hardness: 97a
Road Surface (Millimeters): 29.35
Wheel Width (Millimeters): 37