When a toaster is 600 watts, what do you expect a 150 watt fan heater to do (under ideal conditions, of course)? You don't expect it to warm up the car or the driver. The only thing it might do is defog the window, provided that the airflow is satisfactory. This is not mentioned by the manufacturer, of course. Finally, to explain how weak the 150 watt is, I'll tell you the following: I have an electric car. Now in the winter, when I start to warm up, the power drawn by the heater to warm up the cabin in the first few minutes is 4000 W. Then gradually, the power consumption decreases and reaches about 800 W to maintain the cabin temperature at 20 degrees with external temperatures around 3-4 degrees

It works for 3 minutes and then turns off. Obviously, it overheats immediately. It turns back on after about 20 minutes. Waste of money

Very weak in the hot setting, it takes an hour to warm up.. in the Fan setting it works fine

It doesn't defog - it doesn't heat up even for fun. Don't rely on something like this for a trip, we almost threw them away.