2710.19.06.05 - Containing not more than 500 ppm of sulfur

This HTS classification, 2710.19.06.05, specifically covers distillate and residual fuel oils, including blended fuel oils, that meet precise physical and chemical specifications. These oils are characterized by their API gravity of less than 25 degrees and a Saybolt Universal viscosity at 37.8°C ranging from 45 seconds to 125 seconds. This viscosity range is often associated with what is commercially known as "No. 4-type fuel oils," commonly used in industrial heating and certain types of engines. Critically, this subcategory is defined by its low sulfur content, containing no more than 500 parts per million (ppm) of sulfur.

The distinguishing factor for this classification lies in its sulfur content, differentiating it from its sibling category, 2710.19.06.15, which covers oils with a sulfur content exceeding 500 ppm. Therefore, the determination of whether an oil falls into this category or its sibling hinges on a precise laboratory analysis of its sulfur concentration. Both categories, however, share the same physical characteristics of API gravity and Saybolt viscosity, focusing on a specific range of fuel oil types.

As this is a leaf node in the HTS classification system, there are no further subcategories branching from 2710.19.06.05. This means that any product meeting all the preceding criteria, including the API gravity, viscosity range, and the specified low sulfur content, will be classified directly under this code. The classification is complete at this level, requiring no further subdivision based on additional product characteristics.