Jet-A is jet fuel and is classed as a kerosene fuel, which is somewhere between the gasoline and diesel fractions when distilling crude oil. It's used in aircraft that regularly fly above 35,000 feet above sea level since the actual freezing point of the fuel is -47C. It usually is used with an automatic injection (point of sale) of anti-icing chemical called Prist which simply keeps ice crystals formed from free water in the fuel from freezing in the fuel lines and fuel controller to each engine...