The Rambler® 414 ml / 14 oz. Mug is one of the toughest, most over-engineered camp mugs out there. Unlike traditional camp mugs, this double-wall vacuum-insulated body protects hands from hot or cold contents while keeping coffee, chili, oatmeal -you name it -well-insulated. Like all Rambler Drinkware, the 414 ml / 14oz. Mug and lid are dishwasher safe making them easy to clean. The mug's wide opening means contents are easily accessible, but will cool quicker. That's why the mug comes with the MagSlider Lid, it adds an additional barrier of protection to prevent heat or cold from escaping, but please note -the magnet component is not leakproof and will not prevent spills. Important: Do not place mug over external heat source or open flame. Vacuum seal or other damage may occur.