Mercedes-Benz SLK300 License Plate Bulb Size

The Mercedes-Benz SLK300 license plate light requires a DE3423 bulb size for the specific lighting component located at the rear of the vehicle. Data for the bulb specifications covers the range from 2009 through 2011.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Type	Shop
2009-2011	DE3423	Check Price

Bulb Specifications

Description	Type	Shop
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V.	DE3423	Check Price

Other Locations

Additional Notes

The DE3423 is a festoon-type bulb, meaning it is cylindrical in shape and makes electrical contact through metal caps at each end rather than through a base or pins.
The DE3423 has a nominal length of 41mm, which is the span between its two end contacts and determines physical fitment within the license plate lamp housing.
The bulb operates at 12 volts, consistent with the standard electrical system voltage found in passenger vehicles.
The DE3423 designation follows ANSI standards recognized in both the United States and Canada, indicating the bulb meets a defined set of dimensional and performance criteria within those markets.
The Mercedes-Benz SLK300 uses the DE3423 for its license plate bulb position across the 2009-2011 model years.
Because festoon bulbs are sized by their contact-to-contact length, substituting a festoon bulb of a different length, such as a 36mm or 44mm unit, would result in an improper fit even if the voltage rating matched.