For Brown PRT2000 Digital Thermometer there is not much to say. Two buttons are required for operation. Once the on / off button and the button for the choice of the age (0-3, 3-36- 36+) by the user. After the thermometer for measuring stopping or inserting wait until it beeps and read the temperature. A note from a medical perspective, which is unfortunately not included in the manual. Electronic automatic thermometer should be preheated at least 30 seconds for a correct measurement. The measuring head is in generally a distinct lower temperature (usually room temperature of around 20 degrees), when the measurement environment (35 to 38 degrees). If you switch the electric automatic thermometer as described in the manual directly, then it leads to the measuring point and measures immediately, the result can be displayed to 0.5 degrees lower. So always preheat, otherwise it just weighs in young children a false sense of security. Just try it a try. Thermometer enable and measure directly in the armpit. After the thermometer kept under the arm and repeat the measurements. You will notice a continuous rise in temperature. With proper professional equipment the interval measurements are therefore also taken much longer to allow for this range of adjustment. When Brown PRT2000 set as with most automatic thermometers for the private sector to measure intervals too soon. So preheat!