Review on High-performance Fdit PTC Car Fan Air 🔥 Heater (12V 100W) - Ideal for Compact Room Spaces by Beth Finlinson

If the heating element and fan run on 12V I wouldn't call it a heater. The fan is blowing too much air for the element to get hot enough. However, if you're running a 5V fan or similar, the element can heat up a lot more, and it generates heat well. Being a PTC heating element, once it reaches a certain temperature it will stop producing heat as the resistance through the element increases as it heats up. You need to know what you are doing as it is not really a plug and play heater. Just make sure you have a power source that can handle the roughly 8 amps required.