Do

• Let the product shot dominate: 16:9, at least 70% of the content width, on the plain page or surface colour.
• Keep the headline to the product name or a 2–5 word line.
• Under the shot, a row of 3–4 specs (figure over label, e.g. '19 dB' / 'at full speed') separated by vertical rules.
• End with price (or availability) next to one primary CTA.

Don't

• Don't put a coloured glow, gradient or blurred blob behind the product.
• Don't add a subhead paragraph and two buttons — specs replace the paragraph.
• Don't use lifestyle photography here; it is a clean product shot.

Phone width

• Shot at 4:3 full width; specs become a 2×2 grid; price above a full-width CTA.