by inserting in numerical sequence the following new heading: 9902.30.62 Heavy duty bearing housings, shell cast and sand molded of gray cast iron, machine finished, designed for compression-ignition internal combustion diesel engines, such engines with cylinder capacity of 10 liters or more but not exceeding 16 liters, each bearing housing with an overall length between 55 mm and 135 mm and weighing 6 kg or more but not exceeding 25 kg (provided for in subheading 8483.30.80) Free No change No change On or before 12/31/2025 . 12042. Fixed ration gear boxes Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.30.63 Fixed ratio gearboxes designed for use with generating sets of heading 8502 (provided for in subheading 8483.40.50) 2.4% No change No change On or before 12/31/2025 . 12043. Track drive gear boxes Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.30.64 Track drive gear boxes, designed for use in machinery of heading 8429 or 8436 (provided for in subheading 8483.40.50) 1.5% No change No change On or before 12/31/2025 . 12044. Swing bearing assembly Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.30.65 Geared swing bearing assemblies, of a kind used to rotate the cab of machinery described in subheading 8429.52.10 (provided for in subheading 8483.90.50) 1.5% No change No change On or before 12/31/2025 . 12045. Gears for use in machinery or within engines Subchapter II of chapter 99 is amended by inserting in numerical sequence the following new heading: 9902.30.66 Transmission timing gears or gear drive gears, the foregoing of alloy steel and designed to be used in machinery or within an engine, such gears each weighing between 1.885 kg and 500 kg, measuring between 30 mm and 505 mm in diameter and between 15 mm and 285 mm in width (provided for in subheading 8483.90.50) Free No change No change On or before 12/31/2025 . 12046. 14Y stepper