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Electrical & Lighting / BUYING REFERENCE

G9 LED bulbs: capsule size, output and dimming

Choose a G9 LED capsule by the fitting's specified cap and supply, then check its body dimensions, light output and dimming. A G9 marking does not mean every capsule has the same size. The Philips UK examples below include 43 mm and 52 mm heights, and both dimmable and non-dimmable products. Keep G9 separate from G4: the named G9 examples specify AC 220–240 V, while the separate G4 reference uses an AC electronic 12 V supply.

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Search results. Match the specifications below to the selected listing.

Three G9 capsules with distinct specifications

All three references specify 2700 K light and AC 220–240 V. Their common cap does not remove the differences shown here. Read the product dimensions rather than the larger carton measurements listed elsewhere on the manufacturer's page.

Three G9 capsules with distinct specifications
Philips UK EANOutput / actual powerDimmableBulb height × widthManufacturer source
8720169301634220 lm / 1.9 WNo43 × 14 mmManufacturer reference ↗
8720169301610300 lm / 2.7 WYes; check control compatibility52 × 16 mmManufacturer reference ↗
8720169301696470 lm / 3.7 WNo52 × 16 mmManufacturer reference ↗

Check clearance as well as the connection

The 300 lm dimmable capsule is taller and wider than the 220 lm non-dimmable reference. The cap therefore cannot answer whether a replacement clears a cover or shade. Compare the fitting's permitted lamp dimensions and conditions with the exact replacement, rather than assuming an LED capsule matches the previous lamp's body.

The 25 W and 40 W labels in these product names are equivalence figures. Their actual consumption is listed separately in the table. Use lumens when comparing output; neither the cap code nor the word LED specifies a particular brightness.

G4 is a different replacement question

Philips G4 reference 8720169300491 lists AC electronic 12 V. That is not the supply specification of the G9 examples above. Similar capsule shapes do not establish interchangeability, and this reference does not prescribe changing the fitting or its electrical equipment.

For a dimmed fitting, require a dimmable product and check the lamp manufacturer's compatibility information for the installed control. Keep the full G9 article code, required output, dimensions and dimming status in the Amazon comparison. Confirm the actual selected variant and bulb quantity before buying; a broad G9 search may mix products with different specifications.

Comparison sources

Manufacturer references checked 2026-10-03. These examples describe published specifications, rather than a hands-on review.

MATCH THE DETAILS TO YOUR JOB

What to check before buying

  1. Match the fitting's G9 cap and rated supply; do not treat G4 capsules as substitutes.
  2. Check overall bulb height and width against the permitted space.
  3. Compare lumen output and actual power separately from wattage-equivalence labels.
  4. Verify dimming status and the exact control's compatibility where required.
  5. Keep the full EAN and confirm the selected pack quantity.

Compare the related product types

LED bulb caps, shapes and sizes →E27 LED bulbs: output, dimensions and dimming →GU10 LED bulbs: beam, brightness and dimming checks →

Reference & scope

Philips UK G9 capsule dimensions, voltage, output and dimming

This page is a selection checklist for a product type. The manufacturer instructions and exact retailer listing determine suitability, included accessories and available variants.

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