Instruments & Apparatus Using Optical Radiation (NES)

A refractometer that measures refractive index using optical radiation and does not function as a spectrometer or spectrophotometer is a strong candidate for 87445. However, if the device also performs automatic regulation of a process parameter, it may shift to a regulating apparatus heading. The distinction between measurement-only and measurement-plus-control is critical, and the instrument's technical specification sheet should be reviewed against the full SITC schedule.

87445 is explicitly N.E.S., meaning it applies only after ruling out more specific optical instrument headings—including spectrometers (87443), microscopes, and photographic instruments classified in other parts of the schedule. Importers dealing with multi-function optical platforms should map each function to the schedule systematically, as the principal-function rule determines which heading governs when a device spans multiple categories.