High-Efficiency UI Stacked Transformer Core from China

UI-shaped silicon steel laminations stacked and hinged for easy assembly in high-efficiency transformers used in renewable energy inverters. These cores meet DOE efficiency standards when fully assembled. HTS 8504.90.96.38 covers such pre-stacked configurations.

Duty Rate — China → United States

35%

Rate breakdown

9903.03.0110%Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
9903.88.0125%Except as provided in headings 9903.88.05, 9903.88.06, 9903.88.07, 9903.88.08, 9903.88.10, 9903.88.11, 9903.88.14, 9903.88.19, 9903.88.50, 9903.88.52, 9903.88.58, 9903.88.60, 9903.88.62, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(a) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(b) [to this subchapter]

Import Tips

Efficiency class documentation (e.g

NEMA standards) supports high-efficiency claims during customs review

Hinge mechanism details must show temporary assembly only—no permanent fixtures for parts status

Mark packages with 'For 50/60Hz transformer incorporation only' to prevent misuse classification