Unlike Traditional Camp Mugs; This 340Ml Double-Wall Vacuum-Insulated Body Protects Hands From Hot Or Cold Contents While Keeping Coffee Or Tea; You Name It; Well Insulated. The Mugs Wide Opening Means Contents Are Easily Accessible. The Mug Comes With The Plastic Magnetic Slider Cap; Which Adds An Additional Barrier Of Protection To Prevent Heat Or Cold From Escaping. 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.