With the Swiss Travel Pass Flex Combi, you can freely choose your travelling days. The Swiss Travel Pass Flex is valid for for 3, 4, 8 or 15 days within a month, in which unlimited travel on the Swiss Travel System network is allowed on those days. Furthermore, on the days between the first and the last validated day, the pass offers a 50% discount on trains, buses and boats, as well as half price on most mountain railways.