On or before 12/31/2025 . 11516. Light stabilizer for plastics Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.24.47 Light stabilizer for plastics containing a mixture of (2,2,6,6-tetramethy, 4-piperidinyl) polymer in 50 percent polypropylene (CAS No. 69447–45–8)