What is a festoon bulb?

A festoon bulb is a type of automotive light bulb that is cylindrical in shape with metal caps on both ends. They are commonly used for interior lighting applications such as dome lights, map lights, and vanity mirror lights.

How bright are these LED bulbs?

The SMF1 LED bulb has a measured output of 16 lumens. This provides similar light output to your original 28mm-sized bulb. If you want brighter lights, check out the Diode Dynamics SMF2 option.

What does the warranty cover?

Diode Dynamics offers a three-year replacement warranty on these LED bulbs. If the bulb fails due to a manufacturing defect within that time, they will replace it.

Diode Dynamics

Diode Dynamics 28mm SMF1 LED Bulb - Cool - White (Pair)

Name: Diode Dynamics 28mm SMF1 LED Bulb - Cool - White (Pair)
Brand: Diode Dynamics
Price: 8.14 USD
Availability: InStock

$8.14

Modernize your interior lighting with these direct-fit LED bulbs. Cool white color.

Key Features

Direct replacement — fits any 28mm festoon bulb socket
Modern LED appearance — upgrades from the factory yellowish incandescent bulb
Plug and play — simple installation
Constant-current circuitry — prevents flickering and failure
Transient suppression — protects against voltage spikes
Lightweight design — won't vibrate loose over time

⚠️ CA WARNING: This product can expose you to chemicals known to the State of California to cause cancer and/or birth defects or other reproductive harm. Learn more

Will this fit your vehicle?

Compatible with 218 vehicles

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Product Details

The 28mm SMF1 LED bulb is a direct replacement for any 28mm-size bulb commonly found in vanity mirror lights in many vehicles. The SMF1 upgrades the factory yellowish incandescent bulb to a more modern LED appearance.