Calculate once.
Verify the US path separately.
The shared catalog supplies capacity, output and input limits. The `/en-us` layer adds the facts that cannot safely be inferred from a global product name.
Runtime and output
Runtime remains an estimate based on usable energy, average load and reserve. Continuous output and motor startup are checked separately; stored watt-hours do not prove that a load can start.
US electrical identity
For ordinary household equipment we start with 120V/60Hz and Type A/B context, then verify the exact label, receptacle, grounding instructions and cable. A NEMA shape or plug adapter alone is not evidence of compatibility.
120/240V systems
Split-phase home backup, large loads and transfer equipment require an exact system design. Product output, branch circuit, inlet, transfer equipment, installation and local requirements must agree.
Regional models and commerce
A US manual can support a technical record but does not prove that a listing is the same SKU, seller, warranty or bundle. USD display, US delivery and affiliate tracking are offer-level facts and stay hidden until verified.