90 | | | HS Code for Optical, photographic, cinematographic, measuring, checking, precision, medical or surgical instruments and apparatus; medical-surgical instruments and apparatus; parts and accessories thereof |
| 9032 | | HS Code for Automatic regulating or controlliing instruments and apparatus |
| | 90321000 | Thermostat |
| | 90322000 | Barostat |
| | 90328100 | Instruments and other means of hydraulic or pneumatic |
| | 90328911 | Automatic train protection system (atp) car design |
| | 90328912 | Automatic train operation system (ato) car design |
| | 90328919 | Other automatic train control (atc) car |
| | 90328990 | Other instruments and automatic regulation or control means of a non-hydraulic or pneumatic |
| | 90329000 | Automatic regulating or controlling instruments accessories |
| 9033 | | HS Code for Parts And Accessories (Elsewhere This Group Is Not Named Ilene Included) For Machines, Appliances, Instruments Or Apparatus Of Chapter 90 |
| | 90330000 | Chapter 90 spare parts nes |
91 | | | HS Code for Clocks |
| 9101 | | HS Code for Wrist-watches pocket-watches |
| | 91011100 | Mechanical indication type electronic wrist watch of a noble metal |
| | 91011910 | Optical display type electronic watches noble metal |
| | 91011990 | Other precious metals electronic watches |
| | 91012100 | Noble metal automatic winding mechanical watches |
| | 91012900 | Non-noble metal self-winding mechanical watches |
| | 91019100 | Precious metal pocket watch and other electronic spreadsheet |
| | 91019900 | Precious metals and other mechanical watch mechanical |
| 9102 | | HS Code for Wrist-watches pocket-watches and other watches including stop watches other than those of heading 9101 |
| | 91021100 | Other mechanical indication type electronic watches |
| | 91021200 | Other optical display type electronic watches |
| | 91021900 | Other electronic watches |
| | 91022100 | Other automatic winding mechanical watches |
| | 91022900 | Other non-automatic winding mechanical watches |
| | 91029100 | Electric-powered electronics and other electronic pocket watch |
| | 91029900 | Other mechanical pocket watch, stopwatch and other tables |