Took the classic large on a 3 day kayak camping trip. Weather temps reached the high 80's. The bag held a 20 lb bag of ice with food and some beer for around 36 hrs. Most of the ice was melted but the water from the melted ice stayed cold enough to keep water bottles and beer refreshing up to the 2nd evening of our trip. Definitely would recommend Icemule coolers as I will be purchasing a smaller one for day trips.