Schwalbe's Ice Spiker Performance Line tire is the "turbo" of studded tires. It sports 361 spikes that bite firmly into icy roads. The tungsten carbide core of each spike is clad in weight-saving aluminum. The Ice Spiker is the best way to be agile and sporty while staying upright when the roads ice over. Note: In order to ensure that spikes are permanently fixed, tires should be run in for about 25 miles (40km) on asphalt, while avoiding any fast acceleration or heavy braking.