Winter tyres are specially developed for use in low temperatures and driving in wintry conditions. Their tread blocks have a large number of sipes that ensure sufficient grip even on slick roads. The material compound is also carefully selected to keep the tyres elastic even in the cold. At high temperatures, however, winter tyres become too soft, which is why they should not be used during the summer.
Under German legislation (Road Traffic Licensing Regulation or StVZO), winter tyres must be marked with the M+S symbol. Individuals looking for additional safety with regard to the good driving and braking properties of winter tyres should only purchase models with the snowflake symbol. "Snow tyre" means a tyre whose tread pattern, tread compound or structure are primarily designed to achieve in snow conditions a performance better than that of a normal tyre with regard to its ability to initiate or maintain vehicle motion. Germany does not stipulate a specific time at which winter tyres must be used. Instead, drivers have a duty to switch to winter tyres if driving conditions call for it. In wintry conditions (i.e. black ice, packed snow, snow slush or icy roads), only vehicles with M+S tyres are permitted on the roads. Individuals who do not drive in snow and ice can, in theory, continue using summer tyres even in wintertime. However, as summer tyres have material compounds specially developed for hot conditions, their use during winter is extremely dangerous and not recommended!