Abstract: In known heat-emitting units (1) for car seats the unit (1) is heated to a set temperature and once this has been reached the temperature in the unit (1) oscillates around that set. This is a drawback since, after a certain amount of oscillation, the heat becomes too high and the setting must be altered. According to the invention the voltage supply is cut by means of a recording member (7), after a predetermined period of oscillation.

Abstract: It has been found that in heating pads for seats, preferably car-seats, in which the heating pad (1 and 2) covers both seat and back-rest, an energy recoil from the back-rest may occur. The invention reduces said recoil by dimensioning the resistance wire (11) in the section (4 and 6) of the heating pad (1 and 2) covering the seat and of the resistance wire (10) in the section (3 and 5) of the heating pad (1 and 2) covering the back-rest in such a way that the ratio between the resistance of the first-mentioned resistance wire (11) and that of the last-mentioned resistance wire (10) increases when current flows through.