BMW M6 License Plate Bulb Size

The BMW M6 license plate light requires bulb size 12961 or DE3423 depending on the specific application. Data for the bulb sizes covers the range from 1987 through 2010.

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 Size
2006-2010	12961
1987-1988	DE3423

Bulb Specifications

Description	Bulb Size
Philips part number. Miniature wedge bulb (T10) with W2.1x9.5d base. 12V, 5W.	12961
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V.	DE3423

Other Locations

Additional Notes

The BMW M6 license plate position uses two distinct bulb types across its model years: the 12961 (T10 wedge) for the 2006-2010 model years and the DE3423 (festoon) for the 1987-1988 model years.
The 12961 is a Philips part number designation for a T10 miniature wedge bulb. It operates at 12 volts and draws 5 watts, with a W2.1x9.5d wedge base that requires no socket locking mechanism, as the base itself wedges into the housing.
The DE3423 is an ANSI-standard festoon bulb recognized across the United States and Canada. It measures 41mm in length and makes electrical contact through metal end caps at both terminals rather than through a wedge or pin base.
The W2.1x9.5d base of the 12961 bulb is not interchangeable with the end-cap contact design of the DE3423 festoon bulb. The two types use fundamentally different retention and contact methods, making cross-substitution between the 1987-1988 and 2006-2010 fitments incompatible.
Both bulb types operate on a 12-volt electrical system, which is standard for passenger vehicle lighting circuits. The shared voltage rating does not indicate physical or functional interchangeability between the two base types.
The 12961's 5-watt rating places it in the low-wattage category typical of license plate illumination, where heat output and current draw are kept minimal due to the enclosed nature of the lamp housing.
The DE3423 festoon format is common in applications where a tubular bulb spanning two contact points is required. The 41mm length is a specific fitment parameter, and festoon bulbs of differing lengths will not seat correctly in the same housing.