PTC stands for positive temperature coefficient. There are two kinds of PTC resistors, one is ceramic PTC resistor, which is a positive temperature coefficient thermistor, and it has over-current protection, degaussing, heater, etc., and the other is polymer organic PTC, commonly known as self-recovery fuse. The PTC heater should be a resistor that plays a heating role in ceramic PTC. Can be made into various shapes according to requirements.