The REM-POD is famous from paranormal TV shows. It's a great instrument for researching the paranormal! It is often featured in shows such as Ghost Adventures. The REM-POD emits a low EM field and will alert with both LED lights and an audible tone of any possible spirit activity around it since it reacts to energy changes in its proximity. There is a choice 4 different ranges that the REM-POD will pick up energy changes for. The REM-POD also has ATDD function. ATDD = Ambient Temperature Deviation Detection. If the temperature surrounding the REM-POD increases or decreases, the REM-POD will alert you for every 5/-5 degrees Fahrenheit. There is a button to push to calibrate the REM-POD to the current room temperature.