Kumho Ecsta SPT KU31 XRP Run Flat High Performance Tire - 225/50R17  94Z Extended run-flat performance (50 miles at 50mph) in the event of a puncture Combines strong dry and wet grip, low noise, and long life with run-flat peace of mind High dispersion silica compound for extended tread life Four circumferential grooves for maximum water evacuation Not designed for near-freezing or snow driving conditions