No matter how cold it is outdoors, pouring coffee, tea, or beverages into an Ember Mug can keep you warm all day. It allows an exact drinking temperature ranging from 120°F - 145°F (50°C - 62.5 °C) on the actual mug or with the Ember app. The Smart Mug even has a built-in auto-sleep function that brilliantly detects when to shut on and off, and the Ember Mug maintains the temperature chosen for up to 1.5 hours when off the charging coaster. How cool is this “Hot” item!