The IceMule Classic cooler is a protected, waterproof roll-top bag that carries comfortably and conveniently with a sling strap. The IceMule Classic comes in three sizes and three different colors: 10L (small), 15L (medium), and 20L (large). Each size is available in either orange, olive, or sky blue. It is truly incredible how ingenious these things are and how well they perform – once you roll the top down a few times and buckle it together, you have a fully insulated, waterproof bag that will keep your drinks as frigid as can be all the way to your destination. The IceMule Classic is able to retain ice for 24 hours. Once you are out in the heat and sunshine it will be more like 6-8 hours before your ice starts significantly melting.