Ring details Attention： 1.Make sure your surrounding temperature is not too hot or too cold. 2.Do not wear it when shower or swimming. 3.The digital only shows the temperature around finger It's not a professional therrnorrneter. 4.If you feel ill,please use professional thermometer and take correct medical care 5. If the ring temperature is lower than 27°C, the number will not appear make sure your finger is warm up to normal condieion In winter, the temperature is low, and the ring is made of stainless steel. The heat transfer is slow, and the number may be displayed very slowly. You can immerse it in hot water to quickly display the number.about the actual temperature: I have 28 degrees, although the body temperature is 36,6 and this is natural T. K. The design of the ring uses a standard thermal tape of thermal releases, without any calibration and amendments to the fact that the ring on the inside is heated by the surface of the skin of the finger (which is already below the body temperature) and outside-dissipates the temperature into the environment. So the ring is not an active wearable real-time thermometer, but a keychain is a thermometer that needs to be immersed in the measured environment. You want to measure the temperature in the room-take off the ring and leave for 10 minutes to lie down. You want to measure the body temperature-put the armpit for 2-3 minutes, you can measure the water temperature in the baby bath (reacts quickly, in a few seconds). So almost is a rough thermometer, which is always at hand) use correctly.- When you wear a ring on your finger for 20-30 seconds, it automatically displays the ceramic with temperature.