Application for Further Review of Protest No. 5301-23-109539; Classification of Aluminum “Clamps” for Certain Solar Panel Tracking Systems

H338730 February 6, 2026 OT:RR:CTF:EMAIN H338730 MFT CATEGORY: Classification TARIFF NO.: 8479.90.95 Center Director, Base Metals C.E.E. Port of Houston U.S. Customs and Border Protection 7141 Office City Dr. Houston, TX 77087 Re: Application for Further Review of Protest No. 5301-23-109539; Classification of Aluminum “Clamps” for Certain Solar Panel Tracking Systems Dear Center Director: The following is our decision on the Application for Further Review (AFR) of Protest No. 5301-23-109539, which was filed on November 28, 2023, on behalf of Array Technologies, Incorporated (protestant). The protest pertains to the classification under the Harmonized Tariff Schedule of the United States (HTSUS) by U.S. Customs and Border Protection (CBP) of certain aluminum “clamps” for solar panel tracking systems. For the reasons expressed herein, we find that the subject merchandise is properly classified as “parts” of machines having individual functions not specified or included elsewhere. In reaching this determination, we have considered information presented in the protestant’s original submission; a supplemental presentation and video provided on October 25, 2024; as well as information provided during the conference between counsel for the protestant and CBP held on October 29, 2024. FACTS: The protestant describes the subject merchandise as aluminum clamps from China incorporated after importation into the protestant’s motorized solar panel tracking systems. The solar panel tracking systems are machines that rotate a series of solar panels to follow the movement of the sun throughout the day. This rotation helps maximize the amount of sunlight each solar panel receives, thereby optimizing the generation of solar power. The subject aluminum “clamps” are designed solely for use with the protestant’s solar panel tracking systems but are imported separately from the other materials that are assembled to make the finished system. They have an octagonal opening for placement on an octagonal, hollow, torque beam of steel. To secure the clamp to the torque beam, a long carriage bolt is inserted through one end of the clamp and tightened by a nut on the opposite end. Solar panel frames containing the modules are placed and fixed underneath angled “ears” located on each end of the clamp. During operation, a motor on the solar panel tracking system engages, transferring rotary motion to the torque beam, then to the aluminum clamp attached to the beam, and, ultimately, to the solar panel. This protest includes six entries made between July 7, 2022, and August 5, 2022. Originally, the protestant entered the subject merchandise under heading 7610, HTSUS, which provides for, inter alia, “parts of structures (for example, bridges and bridge-sections, towers, lattice masts, roofs, roofing frameworks, doors and windows and their frames and thresholds for doors, balustrades, pillars and columns)... prepared for use in structures.” CBP liquidated the subject entries under that heading between June 2, 2023, and June 30, 2023. The protestant filed the subject Protest and AFR on November 28, 2023. The protestant primarily argues that the subject merchandise is properly classified under heading 8479, HTSUS, which provides for, “Machines and mechanical appliances having individual functions, not specified or included elsewhere in this chapter; parts thereof.” Alternatively, the protestant argues that the subject merchandise could be classified under heading 7616, HTSUS, which provides for, “Other articles of aluminum.” ISSUE: Whether the subject aluminum clamps are classified under heading 7610, HTSUS, as “parts of structures”; heading 7616, HTSUS, as “[o]ther articles of aluminum”; or heading 8479, HTSUS, as “parts” of machines having individual functions, not specified or included elsewhere. LAW AND ANALYSIS: A decision on classification and the rate and amount of duties chargeable is a protestable matter under 19 U.S.C. § 1514(a)(2). The subject protest was timely filed on November 28, 2023, within 180 days of liquidation, pursuant to 19 U.S.C § 1514(c)(3). Further review of Protest No. 5301-23-109539 is properly accorded to the protestant pursuant to 19 C.F.R. § 174.24(b) because the decision against which the protest was filed is alleged to involve questions of law or fact which have not been ruled upon by the Commissioner of CBP or his designee or by the Customs courts. Specifically, the protestant rightly claims that neither CBP nor the courts have addressed the question of the classification of aluminum clamps for motorized solar panel tracking systems. Classification under the HTSUS is in accordance with the General Rules of Interpretation (GRIs). GRI 1 provides that the classification of goods will be determined according to the terms of the headings of the tariff schedule and any relative section or chapter notes. In the event that the goods cannot be classified solely on the basis of GRI 1, and if the headings and legal notes do not otherwise require, the remaining GRIs 2 through 6 will then be applied in order. 2 The Harmonized Commodity Description and Coding System Explanatory Notes (ENs) constitute the official interpretation of the Harmonized System at the international level. While neither legally binding nor dispositive, the ENs provide a commentary on the scope of each heading of the HTSUS and are generally indicative of the proper interpretation of these headings.1 The HTSUS headings under consideration are as follows: 7610 Aluminum structures (excluding prefabricated buildings of heading 9406) and parts of structures (for example, bridges and bridge-sections, towers, lattice masts, roofs, roofing frameworks, doors and windows and their frames and thresholds for doors, balustrades, pillars and columns); aluminum plates, rods, profiles, tubes and the like, prepared for use in structures. * * * * * 7616 Other articles of aluminum. * * * * * 8479 Machines and mechanical appliances having individual functions, not specified or included elsewhere in this chapter; parts thereof. The primary question is whether the subject merchandise is classifiable as “parts” of a machine of heading 8479, HTSUS. The EN to heading 7610, HTSUS, provides in part that “[t]he heading does not cover [. . .] [c]onstructions clearly identifiable as machinery parts (Section XVI).” Moreover, the EN to heading 7616, HTSUS, provides in part that “[t]his heading covers all articles of aluminum other than those covered by the preceding headings of this Chapter, or by Note 1 to Section XV, or articles specified or included in Chapter 82 or 83, or more specifically covered elsewhere in the Nomenclature” (emphasis added). Therefore, if the subject aluminum clamps are clearly identifiable as machinery “parts” of heading 8479, HTSUS, and are thus provided elsewhere in the tariff, they cannot be classified under either heading 7610 or 7616, HTSUS. The term “part” is not defined in the HTSUS. The courts have considered the nature of “parts” under the HTSUS, and two distinct though not inconsistent tests have resulted.2 The first, articulated in United States v. Willoughby Camera Stores, Inc., (“Willoughby”), 21 C.C.P.A. 322, 324 (1933), requires a determination of whether the imported item is an “integral, constituent, or component part, without which the article to which it is to be joined, could not function as such article.”3 The second, set forth in United States v. Pompeo, (“Pompeo”), 43 C.C.P.A. 9, 14 (1955), provides that when an imported item is dedicated solely for use with another article, and when applied to that use, the item meets the definition of a “part” established in Willoughby, the item constitutes a “part” of the article. Under either line of cases, an imported item is not a part if it is “a distinct and separate commercial entity.”4 There is no dispute that the subject merchandise is designed solely for use with the protestant’s solar panel tracking systems. Both the Willoughby and Pompeo tests require a showing that, without these components, a solar panel tracking system cannot function as such a 1 See Treasury Decision (T.D.) 89-80, 54 Fed. Reg. 35127, 35127–28 (Aug. 23, 1989). 2 See Bauerhin Tech’s Ltd. v. United States, 110 F.3d 774, 779 (Fed. Cir. 1997). 3 See Bauerhin, 110 F.3d at 778 (quoting Willoughby, supra. 4 See Baxter Healthcare Corp. v. United States, 182 F.3d 1333, 1338–39 (Fed. Cir. 1999) (quoting Willoughby, 21 C.C.P.A. at 325). 3 system. This inquiry thus turns on what function the aluminum clamps perform within the solar panel tracking system. As discussed above, the function of a solar panel tracking system is to rotate a series of solar panels to follow the movement of the sun throughout the day. Their role in that process is to secure the solar panel modules to the rest of the machine and transmit rotary motion to the panels. If the components were missing from the solar panel tracking system, the solar panels would not receive that rotary motion. Without this rotary motion, the solar panels will not rotate, and the solar panel tracking system cannot perform its intended function. As such, the subject aluminum components are “integral” to the solar panel tracking system and satisfy both the Willoughby and Pompeo tests. Since the aluminum clamps satisfy both the Willoughby and Pompeo tests, the subject merchandise are “parts” of heading 8479, HTSUS. The clear nature of the aluminum clamps’ functioning and role in helping to rotate the solar panels make them “clearly identifiable” as parts of heading 8479, HTSUS. Because the aluminum clamps constitute, and are clearly identifiable as, “parts” of heading 8479, HTSUS, they cannot be classified under either headings 7610 or 7616, HTSUS. HOLDING: By application of GRIs 1 (Note 2(b) to Section XVI) and 6, the subject aluminum clamps are classified under heading 8479, HTSUS, specifically subheading 8479.90.95, HTSUS, which provides for, “Machines and mechanical appliances having individual functions, not specified or included elsewhere in this chapter; parts thereof: Parts: Other.” The general column one rate of duty is free. This ruling does not address the applicability of any additional duties that may apply to the goods discussed herein.?Likewise, duty rates are provided for your convenience and are subject to change. The text of the most recent HTSUS and the accompanying duty rates are provided at www.usitc.gov. You are instructed to GRANT the Protest. Sixty days from the date of the decision, the Office of Trade, Regulations and Rulings, will make the decision available to CBP personnel, and to the public on the CBP website at www.cbp.gov, by means of the Freedom of Information Act, and other methods of public distribution. Sincerely, for Yuliya A. Gulis, Director Commercial and Trade Facilitation Division 4