This earthquake alarm responds to the sound of an emergency earthquake that flows through the FM radio, and it automatically expands at a loud volume of 85 dB (volume at the same level as in the subway or train) to notify you that an earthquake will soon come. Safe to use, even when you are not wearing a TV or watching video. There is no need to pay for usage and other costs. The annual electricity bill (standby 24/7 per day) is about 154 yen (based on estimated unit cost of 22 yen/kwh).