Michelin Soft directional radial grooved slick utilized for wet surfaces in an ambient air temperatures of 36-70 degrees F. Recommended for utilization at operating tire temperatures of 75-140 degrees F. Designed to operate at pressures from 30 to 32 PSI hot with the recommended cold pressure of 22 PSI (as a starting point which can be fine-tuned to your cars set-up and driving style). Latest generation, recommended usage for Radical SR3 and SR8 race cars rear application.