9017.20 - Other drawing, marking-out or mathematical calculating instruments:

This HTS category, 9017.20, encompasses a range of drawing, marking-out, and mathematical calculating instruments that are not specifically covered by other headings within Chapter 90. It serves as a residual category for instruments used in technical drawing, drafting, and calculation. The primary function of items classified here is to aid in the precise creation of drawings, the accurate marking of lines or points, or the performance of mathematical computations.

It is important to distinguish 9017.20 from its sibling categories. Unlike 9017.10, which specifically covers drafting tables and machines, this category is for handheld or desk-based instruments. It also differs from 9017.30, which is exclusively for micrometers, calipers, and gauges used for length measurement. Items within 9017.20 are not designed for direct linear measurement in the same way as those in 9017.30, nor are they the larger drafting equipment of 9017.10.

This category is further subdivided to provide more granular classification. The subcategories include specific types of mathematical calculators such as disc calculators and slide rules (9017.20.40.00), as well as plotters (9017.20.70.00) used for automated drawing. The residual "Other" subcategory (9017.20.80) captures any remaining drawing, marking-out, or mathematical calculating instruments that do not fit into the more specific sub-classifications, ensuring comprehensive coverage within the broader scope of 9017.20.