Classification follows the machine's principal use as documented by the manufacturer. A machine marketed and configured primarily for metal testing — with metal-specific grips, load cells, and software — typically falls under 9024.10 even if it can physically accommodate polymer specimens. If the machine is genuinely multi-material with no dominant application, 9024.80 (NESOI) is the fallback. Binding ruling requests to CBP are advisable for dual-use universal testers.

Machines classified under 9024100000 are not broadly subject to Section 232 steel or aluminum tariffs, as those apply to the metals themselves rather than testing equipment. However, importers sourcing from certain origins should verify current Section 301 exposure and any applicable antidumping or countervailing duty orders at the time of entry, as trade-remedy coverage can change.