HSD is a complex mixture of Hydro Carbons. It is a brown colored oily liquid with pungent smell. MPRL domestically mainly markets two grades of HSD namely BS-III and BS-IV .The main difference between BS-III and BS-IV is Sulphur content, i.e. for BS-III 350 ppm and BS-IV 50 ppm.

Diesel engines are used in cars, motorcycles, boats and locomotives. Automotive diesel fuel serves to power trains, buses, trucks, and automobiles, to run construction, petroleum drilling and other off-road equipment and to be the prime mover in a wide range of power generation and pumping applications. HSD is normally used as a fuel in medium and high speed compression ignition engines (operating above 750 rpm) in commercial vehicles, stationary diesel engines, locomotives and pumps etc.