a device for regulating body temperature includes a case with an opening in the base , a plate made of highly thermally conductive material with a complementary shaped protrusion at the opening and that is inserted therein , at least a peltier cell , an electronic circuit board for managing the functions of the device , a heat sink , a display , a battery to power the electronic circuit board , the peltier cell and the display , a temperature sensor to measure the temperature of the skin at the surface of the case and of the plate that is in contact with the skin , a strap which is secured to said concave case , a lid for closing said case , and at least one command button operatively connected to the electronic circuit board .