Sulphur free gas oil or SFGO is an eco-friendly gas oil. SFGO has a much lower sulphur level of only 10 parts per million. This fuel is used for non-road mobile machinery (NRMM) such as tractors, excavators, quarrying equipment, etc. It is dyed green in the same way as marked gas oil.
Due to the low sulphur content this fuel is better for the environment and some modern tractors now specifically require this product.