. 1204. Modified acrylic flame retardant staple fiber with a decitex of 3.9 Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.13.22 Modacrylic staple fibers, not carded, combed or otherwise processed for spinning, containing over 35 percent and less than 85 percent by weight of acrylonitrile, 3.9 decitex (plus or minus 2 percent), natural in color, with fiber length between 38 mm and 120 mm (provided for in subheading 5503.30.00) Free No change No change On or before 12/31/2020 . 1205. Acrylic fiber staple, dyed Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.13.23 Acrylic staple fiber (polyacrylonitrile staple), dyed, not carded, combed or otherwise processed for spinning, the foregoing containing by weight 92 percent or more of polyacrylonitrile, not more than 0.01 percent of zinc and 2 percent or more but not over 8 percent of water, with a decitex of 3.3 to 5.6, a fiber shrinkage of from 0 to 22 percent (provided for in subheading 5503.30.00) Free No change No change On or before 12/31/2020 . 1206. Flame retardant rayon fiber Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.13.24 Artificial staple fibers of viscose rayon, not carded, combed or otherwise processed for spinning and containing 28 percent or more but not over 33 percent by weight of silica (provided for in subheading 5504.10.00)