What is a festoon bulb?

A festoon bulb is a type of automotive 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 does the light output of this bulb compare to the original?

The SMF1 LED bulb provides 16 lumens of measured output, which is similar to the light output of your original 28mm-sized bulb. If you want more light, Diode Dynamics recommends their SMF2 option.

How long is the warranty on these bulbs?

Diode Dynamics backs these SMF1 LED bulbs with a three-year replacement warranty. The constant-current circuitry and transient suppression help these bulbs last for years.

Diode Dynamics

Diode Dynamics 28mm SMF1 LED Bulb - Cool - White Set of 4

Name: Diode Dynamics 28mm SMF1 LED Bulb - Cool - White Set of 4
Brand: Diode Dynamics
Price: 16.33 USD
Availability: InStock

$16.33

Direct replacement for 28mm festoon bulbs. Adds a modern LED appearance with simple plug-and-play installation.

Key Features

Direct replacement — fits factory 28mm festoon bulb sockets
Modern LED appearance — upgrades from factory yellowish incandescent bulb
Plug and play — simple installation
Constant-current circuitry — prevents flickering and failure
Transient suppression — extends bulb life
16 lumens output — similar light output to original 28mm bulb

⚠️ 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 193 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.