| Tariff Classification |
| section 18 | Optical, photographic, cinematographic, measuring, checking, precision, medical or surgical instruments and apparatus; clocks and watches; musical instruments; parts and accessories thereof |
| chapter 90 | Optical, photographic, cinematographic, measuring, checking, precision, medical or surgical instruments and apparatus; parts and accessories thereof |
| 9020.00 | Other breathing appliances and gas masks, excluding protective masks having neither mechanical parts nor replaceable filters |
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