The core activity of Grint, Marti & Co. is the production and sale of natural wines from the Bernese Oberland, particularly from the region around Lake Thun. The company operates vineyards in Gunten, where various grape varieties such as Pinot Noir, Nebbiolo, Moscato and Cornalin d'Aoste are cultivated. The wines are produced in the company's own cellar without the addition of sulphur, fermented naturally and unfiltered. The company offers a range of wine varieties, including white, rosé and red wines, and sells them through various sales channels, including direct sales in Gunten and in selected restaurants and wine shops.