Where the numbers come from
For model dimensions, installation methods and electrical details, we prefer the current manufacturer manual, dimension drawing or specification sheet. Retailer pages can help explain the shopping question, but they do not replace the instructions for the exact model.
When two pages disagree
We do not average conflicting measurements or guess a missing value. We check the model number, document date and installation method, then use the clearest current manufacturer information. If the answer still is not clear, the guide says what needs to be checked.
Corrections
If you spot an outdated number or a broken source, email the page URL and the newer document to [email protected]. We review the affected guide, comparison or calculator together.
Affiliate links
Some pages may eventually contain clearly marked affiliate links. A commission will not change a product specification or the way a comparison works.