The measurement principle works very simple: Switch on, choose age group, press device in his ear and the measurement button. Unfortunately, the measured temperature varies by up to 1.5 degrees. I do not know if we have received a defective appliance or whether the differences in measurements are normal. Since we had acquired a favorable ear thermometer from another manufacturer some time ago, which has also measured very inaccurately, we have lost confidence and measure back to normal, as for generations :)
