I love Fjällräven; the company can be credited in many ways to the evolution of the modern book bag and how it distributes weight. The Kanken bags are made from “Vinylon-F” which is a, largely waterproof, synthetic material developed in the 40s. I’ve purchased one of these bags but I’m so far on my second with their stellar warrantee; the first one sat too close to an old gas heater and disintegrated, but Fjällräven was quick to replace it with a brand new bag after I informed them of what happened. I think the traditional look of these coupled with their (relatively decent) durability make them an obvious go-to for everything from school to casual business meetings.