Both digital and vernier calipers are hand-held length-measuring instruments and classify under subheading 901730 alongside micrometers and gauges. The measurement technology — digital readout versus vernier scale — does not change the classification; what matters is that the instrument measures length by direct contact.

Many precision hand-measuring instruments under heading 9017 sourced from China are subject to Section 301 measures. The measure attaches at the specific 10-digit tariff line and country of origin, so importers should verify the applicable list and any granted exclusions for their exact product before entry.