Tongue-and-Groove MDF Subfloor Underlayment from United States

Ultra-thin MDF panels, 3.6 mm in thickness, with interlocking tongue-and-groove edges, used as underlayment beneath vinyl flooring in wall-to-wall building floor preparations. These panels provide a smooth, stable base for flooring installation. They are classified under tariff item 4411.12.00 as MDF of a thickness not exceeding 5 mm, as the underlayment use and edge profiling do not alter their fibreboard classification.