4411.12.20.00 - Laminated boards bonded in whole or in part, or impregnated, with synthetic resins

This HTS category, 4411.12.20.00, specifically classifies medium density fiberboard (MDF) that does not exceed 5 mm in thickness. Crucially, these boards are distinguished by having been tongued, grooved, or rabbetted continuously along any of their edges. This milling process is not for aesthetic purposes alone; the primary characteristic and intended use of these boards is for construction applications, specifically for walls, ceilings, or other building components.

The defining feature of this category, differentiating it from its sibling category 4411.12.30.00 ("Other"), lies in the presence of these continuous edge profiles. While the sibling category would encompass other MDF boards of the same thickness not designed or prepared for specific construction joinery, this category isolates those prepared for inter-locking or fitting into building structures. The "Other" category would therefore include plain-edged MDF boards of this thickness, or those with edge treatments not specifically for building construction.

As this is a leaf node in the HTS classification, there are no further subcategories to introduce. Classification under 4411.12.20.00 is definitive for MDF under 5mm thickness that possesses these continuous tongued, grooved, or rabbetted edges intended for building construction. The presence of these specific edge profiles, coupled with the material and thickness criteria, is sufficient for classification at this level.