Jaguar Super V8 License Plate Bulb Size

The Jaguar Super V8 license plate light requires 12961 and DE3423 bulb sizes for the exterior lighting system. Data for the specified components covers the period from 2005 through 2009.

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
2007-2009	12961
2005-2006	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 Jaguar Super V8 license plate bulb specification changed between the 2005-2006 and 2007-2009 model years, with two distinct bulb types used across the five-year span covered by these specifications.
The 12961 is a Philips part number designating a T10 miniature wedge bulb with a W2.1x9.5d base, rated at 12V and 5W. The W2.1x9.5d base refers to a wedge-style contact system where the bulb glass itself acts as the retaining and contact mechanism, requiring no separate metal base pins.
The 12961 bulb fits the 2007-2009 Jaguar Super V8 license plate position. Its wedge base design is not interchangeable with festoon-style sockets, which use a different physical contact and retention method.
The DE3423 is an ANSI-designated festoon bulb rated at 12V, with a 41mm length and end-cap contacts. End-cap contacts mean the bulb makes electrical contact at both cylindrical ends rather than through a base pin or wedge.
The DE3423 bulb applies to the 2005-2006 Jaguar Super V8 license plate position. Festoon bulbs seat by spring tension between two contact points, a mounting method physically incompatible with wedge-type sockets.
The 41mm length of the DE3423 is a critical fitment factor. Festoon bulbs of differing lengths, such as 36mm or 44mm variants, would not seat correctly in a socket sized for the 41mm specification.
Both bulb types share a 12V operating voltage, consistent with standard automotive electrical systems. However, the wattage of the DE3423 is not stated in these specifications, while the 12961 is explicitly rated at 5W.
The T10 designation of the 12961 refers to the bulb's tubular envelope width of 10/8 inch. This is a widely used size in automotive interior and exterior lighting, though socket compatibility depends on the base type rather than envelope size alone.