SAFE AND RELIABLE: The warmer coaster is composed of high-quality ABS and aluminum materials, which are resistant to high temperature, strong thermal conductivity, safe and durable. TEMPERATURE SETTING: The mug warmer coaster can keep your beverage temperature between 120℉-140℉(40-60℃). Neither too cold nor too hot. It allows you to maintain a constant temperature throughout the day and enjoy hot coffee, tea, drink, etc. at any time. FOR SUITABLE CUP: Suitable for most types of tableware: metal, ceramic, enamel, tile, high temperature plastic, glassware etc. A thin-walled, flat-bottomed mug will have the best warmth retaining performance. NOTE: It does not support to boil liquids, designed to keep your hot drinks in a suitable drinking temp. BEAUTIFUL AND COMPACT DESIGN: 4 x 5 x 0.7 inches, Lightweight and cute, easy to operate, easy to store and carry, suitable for various occasions such as home, work and travel. The best gift to your care to your family, loved ones or friends on Valentine's Day, Thanksgiving, Christmas or other special occasions.