Mercedes-Benz SLK350 License Plate Bulb Size

The Mercedes-Benz SLK350 license plate light requires a bulb size of DE3423 for proper installation and function. Available data covers the specific range from 2005 through 2011 for the mentioned vehicle.

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
2005-2011	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 Mercedes-Benz SLK350 uses the DE3423 bulb for its license plate lights across the 2005-2011 model years.
The DE3423 is a festoon-type bulb, meaning it is cylindrical in form and makes electrical contact through metal caps at both ends rather than through a base socket.
The bulb measures 41mm in length, which is the span between its two end-cap contacts and determines physical fitment within the license plate housing.
The DE3423 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 conforms to a defined set of performance and dimensional criteria shared across those markets.
Because festoon bulbs rely on contact pressure at both ends, the 41mm length is a critical fitment factor. A bulb of a different length may not make reliable contact or may not seat properly within the housing.