This subheading captures purely mechanical devices — such as gear-driven adding machines and abacus-style mechanical counters — as well as electromechanical machines that use electric motors to drive mechanical calculation mechanisms but do not rely on electronic circuits for computation. Modern hybrid devices with any electronic processing component would typically be reclassified under 847021 or 847029.

CBP may request technical specifications, circuit diagrams, or manufacturer declarations confirming the absence of electronic integrated circuits or microprocessors. A detailed product description in the commercial invoice and a technical data sheet are the minimum recommended documentation. For novel or ambiguous designs, a binding ruling request to CBP provides the strongest classification certainty.