;thiocyanate (ammonium thiocyanate) (CAS No. 1762–95–4) (provided for in subheading 2842.90.10) Free No change No change On or before 12/31/2024 . 4141. Modified amine complex of boron trifluoride Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.19.41 Propan-2-amine, compound with trifluoroborane, reaction products with 2-(butoxymethyl)oxirane (amine complex of boron trifluoride) (CAS No. 68478–97–7) (provided for in subheading 2842.90.90) Free No change No change On or before 12/31/2024 . 4142. Trichlorosilane Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.19.42 Trichlorosilicon (CAS No. 10025–78–2) (provided for in subheading 2853.90.90) Free No change No change On or before 12/31/2024 . 4143. 1,3-Dichloropropene Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.19.43 (E)-1,3-Dichloroprop-1-ene (CAS No. 542–75–6) (provided for in subheading 2903.29.00) 2.4% No change No change On or before 12/31/2024 . 4144. Hexafluoroisobutylene (HFIB) Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.19.44 3,3,3-Trifluoro-2-(trifluoromethyl)prop-1-ene (CAS No. 382–10–5) (provided for in subheading 2903.39.20) Free No change No change On or before 12/31/2024 . 4145. 1,1,1,2,2,3,3,4,4,5,5,6,6-Tridecafluoro-8-iodooctane Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.19.45 1,1,1,2,2,3,3,4,4,5,5,6,6-Tridecafluoro-8-iodooctane (CAS No. 2043–57–4) (provided for in subheading 2903.79.90) Free No change No change On or before 12/31/2024 . 4146. Ethyl benzyl chloride Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.19.46 1-(Chloromethyl)-3-ethylbenzene (CAS No. 26968–58–1) (provided for in subheading 2903.99.80) Free No change No change On or before 12/31/2024 . 4147. Perfluoroalkyl sulfonate