The world’s first winter tyre with retractable studs / Nokian Tyres
https://www.nokiantyres.com/innovation/research-and-development/the-world-s-first-winter-tyre-with-retractable-studs/ This looks as an interesting concept: Nokian Tyres presents the world’s first non-studded winter tyre with studs in connection with the 80th anniversary of the winter tyre. With a press of a button, the driver can bring out the studs to improve the grip of the tyre. When the studs are not needed, they →