8481.30.20.90 - Of steel

This HTS category, 8481.30.20.90, specifically covers check (nonreturn) valves that are constructed from steel. These valves are designed to permit flow in only one direction, preventing backflow in piping systems for a wide range of applications, including those involving pipes, boiler shells, tanks, and vats. The "of steel" designation emphasizes that the primary construction material for these specific check valves is steel, distinguishing them based on material composition.

This classification is part of a broader group of check valves and is differentiated from its sibling category, 8481.30.20.10, "Of iron." The key distinction here lies in the material. While both categories fall under "Of iron or steel," this specific code narrows the scope to exclusively steel-made check valves, excluding those predominantly made of iron.

As this is a leaf node within the HTS structure, there are no further subcategories. Therefore, the classification is complete for steel check (nonreturn) valves. When classifying, confirm that the valve's primary material is steel and that its function is solely to prevent reverse flow.