Chapter notes
Harmonized Tariff Schedule of the United States Revision 29 (2025)
Annotated for Statistical Reporting Purposes
CHAPTER 51
WOOL, FINE OR COARSE ANIMAL HAIR;
HORSEHAIR YARN AND WOVEN FABRIC
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Note
1. Throughout the tariff schedule:
(a) "Wool" means the natural fiber grown by sheep or lambs;
(b) "Fine animal hair" means the hair of alpaca, llama, vicuna, camel (including dromedary), yak, Angora, Tibetan, Kashmir or
similar goats (but not common goats), rabbit (including Angora rabbit), hare, beaver, nutria or muskrat; and
(c) "Coarse animal hair" means the hair of animals not mentioned above, excluding brush-making hair and bristles (heading
0502) and horsehair (heading 0511).
Additional U.S. Notes
1. For the purposes of headings 5101, 5102, 5103 and 5104, regarding any package containing wool or fine animal hair subject to
different rates of duty, notwithstanding the rates of duty shown, the column 1 rate of duty is the highest column 1 rate applicable
to any part of the contents of the package comprising not less than 10 percent thereof by weight and the column 2 rate of duty
is the highest column 2 rate applicable to any part of the contents of the package comprising not less than 10 percent thereof
by weight.
2. For the purposes of this chapter:
(a) The term "clean kg" in the rate columns means kilogram of clean yield;
(b) The term "clean yield," except for purposes of carbonized fibers, means the absolute clean content (i.e., all that portion of
the merchandise which consists exclusively of wool or hair free of all vegetable and other foreign material, containing by
weight 12 percent of moisture and 1.5 percent of material removable from the wool or hair by extraction with alcohol, and
having an ash content of not over 0.5 percent by weight), less an allowance, equal by weight to 0.5 percent of the absolute
clean content plus 60 percent of the vegetable matter present, but not exceeding 15 percent by weight of the absolute clean
content, for wool or hair that would ordinarily be lost during commercial cleaning operations;
(c) For purposes of carbonized fibers, the term "clean yield" means in the condition as entered;
(d) (i) The term "wool for special uses" means unimproved wool and other wool of whatever blood or origin not finer than 46s
entered by a dealer, manufacturer or processor, and certified for use only in the manufacture of felt or knit boots, floor
coverings, heavy fulled lumbermen's socks, press cloth, papermakers' felts or pressed felt for polishing plate and mirror
glass;
(ii) Wool for special uses shall not be released from customs custody unless the dealer, manufacturer or processor files a
bond to insure that any wool entered as wool for special uses shall be used only (except as provided below) in the
manufacture of the articles enumerated in subparagraph (i) above;
(iii) A dealer, manufacturer or processor may be relieved of liability under his or her bond with respect to any wool entered
as wool for special uses which is transferred in its imported or any other form to another dealer, manufacturer or processor
who has filed a bond to insure that the merchandise so transferred shall be used only (except as provided below) in the
manufacture of the articles enumerated in subparagraph (i) above;
(iv) When wool entered as wool for special uses is used, or transferred for use, otherwise than in the manufacture of the
articles enumerated in subparagraph (i) above:
(A) the regular duties which would have been applicable to such wool in the condition as entered shall be paid by the
dealer, manufacturer or processor whose bond is charged with the wool at the time of such use or transfer for such
use, but such duties shall not be levied or collected on any waste or byproducts resulting from the usual course of
manufacture of the articles enumerated in subparagraph (i) above or on any merchandise which is destroyed or
exported;
Harmonized Tariff Schedule of the United States Revision 29 (2025)
Annotated for Statistical Reporting Purposes
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Additional U.S. Notes (con.)
(B) if prior to such use or transfer for such use there shall have been combined or mixed with such wool any other
merchandise, the whole of the combination or mixture shall be regarded as being composed of wool entered as
wool for special uses, unless the dealer, manufacturer or processor liable for the payment of the duties shall establish
the quantity of bonded wool in such combination or mixture;
(C) every dealer, manufacturer or processor who has given a bond pursuant to the provisions for wool for special uses
shall report any transfer or use of merchandise contrary to the terms of the bond, within 30 days after such transfer
or use, to the district director of customs in whose district the bond is filed, and for failure to so report such dealer,
manufacturer or processor shall be liable to a penalty (in addition to the duties provided for) equal to the value of
the merchandise so transferred or used at the time and place of such transfer or use; and
(D) the clean yield of any wool shall be deemed to be 100 percent, unless the actual clean yield has been determined
by suitable tests and such use or transfer for use occurs not later than 3 years after the date of entry of such wool;
(e) The term "unimproved wool" means Aleppo, Arabian, Bagdad, Black Spanish, Chinese, Cordova, Cyprus, Donskoi, East
Indian, Ecuadorean, Egyptian, Georgian, Haslock, Iceland, Karakul, Kerry, Manchurian, Mongolian, Oporto, Persian, Pyrenean,
Sardinian, Scotch Blackface, Sistan, Smyrna, Sudan, Syrian, Tibetan, Turkestan, Valparaiso or Welsh Mountain wool and
similar wool not improved by the admixture of merino or English blood; and
(f) The standards for determining grades of wool shall be those which are established from time to time by the Secretary of
Agriculture pursuant to law and which are in effect on the date of importation of the wool.
Harmonized Tariff Schedule of the United States Revision 29 (2025)
Annotated for Statistical Reporting Purposes
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