FOUR is presented by AI GROUP. Founded in November 2004 in Finland. By a car audio enthusiastic who has passion. Products developed by him and fellow enthusiasts. They have competition history all the way from 1990 ́s. Winning several European Championships in their career. Passion to make products that they would have liked to use, products that are designed by people who use them in real life. This is the story of FOUR. And this story will be continued for long.