For a safer journey. You have full control on icy roads with the Marathon Winter. Even in tight bends and under violent braking everything remains under control. The spikes work best on ice when running at minimum pressure, while at maximum pressure the tires can be ridden on ice-free roads with minimal road noise. Tires need to be run-in for 25 miles / 40 km on hard-top road to ensure spikes are permanently fixed. Avoid rapid acceleration and braking during this period. Tungsten carbide core spikes have a wear life of several thousand kilometers. KevlarGuard Reflex sidewall Winter Compound weight 630g 20 x 1.6 950g 40k of asphalt riding without heavy accelerations or braking is recommended to 'set' the studs