Gas Oils are middle distillates, predominantly of carbon number range C11 to C25 and with a distillation range of 160°C to 420°C. Gas oils are obtained from the lowest fraction from atmospheric distillation of crude oil, while heavy gas oils are obtained by vacuum re-distillation of the residual from atmospheric distillation. Gas Oil/Diesel distils between 180°C and 380°C. Several grades are available depending on uses: Gas Oil for Diesel compression ignition (cars, trucks, marine, etc.), light heating oil for industrial and commercial uses and other gas oil including heavy gas oils which distil between 380°C and 540°C and are used as petrochemical feed stocks. Gas oil is defined as: "heavy oil of which not more than 50% by volume distils at a temperature not exceeding 240 degrees Celsius and of which more than 50% by volume distils at a temperature not exceeding 340 degrees Celsius."