(CAS No. 1150560–54–5) (provided for in subheading 2933.59.70) Free No change No change On or before 12/31/2020 . 537. Pyrimisulfan Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.06.44 (RS)-2′-[(4,6-dimethoxypyrimidin-2-yl)(hydroxy)methyl]-1,1-difluoro-6′-(methoxymethyl)methanesulfonanilide (Pyrimisulfan) (CAS No. 221205–90–9) (provided for in subheading 2933.59.80) Free No change No change On or before 12/31/2020 . 538. DMDS Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.06.45 2,2-Dithiobis(8-fluoro-5-methoxy)-1,2,4-triazolo[1,5-c] pyrimidine (CAS No. 166524–74–9) (provided for in subheading 2933.59.95) 1.0% No change No change On or before 12/31/2020 . 539. Triethylenediamine Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.06.46 Triethylenediamine (1,4-diazabicyclo[2.2.2]octane) (CAS No. 280–57–9) (provided for in subheading 2933.59.95) Free No change No change On or before 12/31/2020 . 540. DAT intermediate Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.06.47 5,8-Dimethoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-amine (CAS No. 219715–62–5) (provided for in subheading 2933.59.95) Free No change No change On or before 12/31/2020 . 541. 2-Amino-4,6-dimethylpyrimidine Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.06.48 4,6-Dimethyl-2-pyrimidinamine (CAS No. 767–15–7) (provided for in subheading 2933.59.95) Free No change No change On or before 12/31/2020 . 542. ADTP Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.06.49 2-Amino-5,7-dimethoxy-1,2,4-triazolo[1,5-a]pyrimidine (ADTP) (CAS No. 13223–43–3) (provided for in subheading 2933.59.95) Free No change No change On or before 12/31/2020 . 543. Cyanuric chloride Subchapter II of chapter 99 is amended by inserting in