Free No change No change On or before 12/31/2020 . 1582. Differentials Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.17.04 Differentials for vehicles of heading 8703, each incorporating a self-contained silicone-fluid filled reservoir, shear pump and progressively-locking clutch pack, the foregoing other than for tractors (except road tractors) (provided for in subheading 8708.50.89) 2.4% No change No change On or before 12/31/2020 . 1583. Suspension system stabilizer bars Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.17.05 Suspension system stabilizer bars of alloy steel, weighing not more than 40 kg, designed for use in Class 7 and Class 8 heavy duty trucks only (provided for in subheading 8708.80.65) Free No change No change On or before 12/31/2020 . 1584. Mufflers and exhaust pipes and parts thereof Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.17.06 Mufflers and exhaust pipes for motor vehicles of headings 8701 to 8705 (other than for tractors suitable for agricultural use) (provided for in subheading 8708.92.50) and parts thereof (provided for in subheading 8708.92.75) 2.4% No change No change On or before 12/31/2020 . 1585. Stand-up bicycles Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.17.07 Bicycles each with no seat, no seat tube and no seat stay, designed to be pedaled by a user in a standing position only, such bicycles having both wheels not exceeding 63.5 cm in diameter (provided for in subheading 8712.00.15) 2.7% No change No change On or before 12/31/2020 . 1586. Elliptical cycles Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.17.08 Cycles, each either with two wheels and having both wheels not exceeding 63.5 cm in diameter, or with three wheels