Different sockets can be charged at different resistance levels and too much resistance supplied to an appliance results in heat. Fuses are designed to blow when there is a short circuit or polarity is overturned but most don't have a thermal cut off. The Engel Thermal Fuse performs the same as a regular 10 Amp fuse but has a unique additional feature that makes it stand out from the rest. If your Engel Fridge Freezer cable is found to have too much resistance, and producing lots of heat, the Engel Thermal Fuse is devised to blow at temperatures greater than 70°C. So keep your Engel Fridge Freezer safe and more importantly your drinks cool by making sure you install the Engel Thermal Fuse.