9902.03.19 - Prohexadione-calcium (Calcium bis(3,5-dioxo-4-propionylcyclohexanecarboxylate)) (CAS No. 127277-53-6) (provided for in subheading 2918.30.90)

This HTS category, 9902.03.19, specifically covers Prohexadione-calcium, identified by CAS No. 127277-53-6. Prohexadione-calcium is a plant growth regulator used to control vegetative growth in various agricultural and horticultural applications. Its inclusion under Chapter 99 signifies a temporary legislative provision or modification, indicating that its import may be subject to specific conditions, duties, or restrictions beyond the standard tariff classifications. The parenthetical reference to subheading 2918.30.90 highlights that, in the absence of these temporary provisions, Prohexadione-calcium would typically be classified as a derivative of an aldehyde-alcohol-phenol or their halogenated, sulfonated, nitrated or nitrosated derivatives.

As a leaf node within Chapter 99, this category does not have further subcategories. Its uniqueness lies in its specific designation for Prohexadione-calcium under a special classification provision. Unlike the broad categories found in earlier chapters of the HTS (e.g., live animals, agricultural products), this entry is highly specific and administrative in nature, focusing on a particular chemical compound subject to a temporary trade or regulatory measure. The classification is driven by the product's identity and its adherence to the terms of the special provision.