A digital readout module designed and sold specifically as a replacement for a caliper or micrometer is generally classifiable as a part of a length measuring instrument under this heading, provided it is not a general-purpose display adaptable to other uses. If the module is a standard electronic display component with broad applicability, it may be classified under electronic components headings. Manufacturer documentation confirming dedicated instrument use is the key supporting evidence.

Yes. All imported articles, including small instrument parts, must be marked with the country of origin in a conspicuous location that survives normal handling. For very small components such as micrometer thimbles or caliper jaws, marking the smallest container in which the article reaches the ultimate purchaser is an accepted alternative when direct marking is impractical. Failure to mark correctly can result in additional duties and delays at the port of entry.