Normally, the summer tire worn on a car can run on a dry road surface or a wet road surface, but it is dangerous to slip on a snowy road or a frozen road surface. Studless tires were developed for safe driving in winter. Studless tires are designed to grip even on snowy or frozen road surfaces, so it is an item that must be there in order to travel safely in a car in the area where snow falls. Early developed studless tires were not something that could be used on snowy roads very much. They tried trial and ...