Stackable and shatterproof for worry-free stowing and going. This drop- and dent-resistant mug is loaded with top-to-bottom insulation to keep your coffee piping hot from the first pour to the last sip. Built-in grooves on the bottom let multiple mugs stack perfectly on top of one another for neat, compact storage. Utilizing magnet technology, the crystal-clear, shatterproof plastic MagSlider lid opens and closes smoothly to prevent splashes and keep debris out of your drink.