OTAD x Pressure Wheels feature a new tough, nearly indestructible aluminum core that has been extruded and then CNC machined to perfection. The interlock core design provides a strong bond between the new 88a UHR compound and the core. Long lasting, fast as hell but still super grippy, this is the wheel you want when ripping up the skatepark! Specs: Size: 60mmWheel Diameter: 60mmWheel Hardness: 88aWheel Compound: UHR(Ultra High Rebound)Wheel Profile: RoundWheel Core: AluminumWheel Bearing Standard: 608Wheel Spacer: AL Floating Spacer, 8mmWheel Width: 24mmWheel Manufacturing Process: Cast