;butane-1,4-diol (CAS No. 72828–34–3) (provided for in subheading 3909.50.50) Free No change No change On or before 12/31/2024 . 4735. Blocked polyisocyanate for use in can and coil applications Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.25.49 Isocyanato-1-(isocyanatomethyl)-1,3,3-trimethylcyclohexane (Isophorone diisocyanante), homopolymer, methyl ethyl ketone oxime-blocked (CAS No. 103170–26–9) (provided for in subheading 3909.50.50) Free No change No change On or before 12/31/2024 . 4736. Polydimethylsiloxane Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.25.50 Polydimethylsiloxane (Dimethyl-bis(trimethylsilyloxy)silane) (CAS No. 63148–62–9) (provided for in heading 3910.00.00) Free No change No change On or before 12/31/2024 . 4737. Silicone resins Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.25.51 Siloxanes and silicones, di-Me, polymers with Me PH silsesquioxanes (CAS No. 68440–81–3) (provided for in heading 3910.00.00) Free No change No change On or before 12/31/2024 . 4738. Methoxyfunctional methyl-phenyl polysiloxane Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.25.52 Siloxanes and silicones, di-Me, polymers with PH silsesquioxanes, butoxy- and methoxy-terminated (CAS No. 104780–72–5) (provided for in heading 3910.00.00) Free No change No change On or before 12/31/2024 . 4739. Hydrogenpolysiloxane Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.25.53 Dimethyl-[methyl(trimethylsilyloxy)silyl]oxy-trimethylsilyloxysilane (CAS No. 68037–59–2) (provided for in heading 3910.00.00) Free No change No change On or before 12/31/2024 . 4740. Methyl silicone resins Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.25.54 Siloxanes and silicones, di-Me, polymers with