Primus Polycarbonate Double Walled Insulated Thermal Commuter Mug holds 0.4 l (14 oz) of your favorite beverage. Silicone seals insure no spills, just click to open & seal it with one simple button. It accommodates a wide variety of car cup holders. The Primus commuter mug is also watertight, so it can be put into a pack or rucksack.