Product type	Where to look
TVs & Home Theater	The sticker is on the back panel of the TV, often near the ports. Most smart TVs also show the model code in the settings menu under Support or About, which is easier than pulling a mounted TV off the wall.
Headphones & Speakers	Earbuds print a small model code inside the charging case lid or on the stem. Headphones use the inside of the headband.

Getting the official Denon manual

Denon publishes product documentation on denon.com. Search there with the full model number from the label, then look for a documents, manuals or downloads section on the product page.

If your model isn't listed, try removing the last few characters, which usually only indicate color or region. For discontinued models, look for an archive or legacy products section, or contact Denon support directly.