Ram ProMaster License Plate Bulb Size

The Ram ProMaster license plate bulb uses a 12961 or DE3423 bulb size for this vehicle model. The replacement chart covers 2014 through 2021 production years with corresponding bulb size specifications.

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
2021	12961	Check Price
2014-2018	DE3423	Check Price

Bulb Specifications

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

Other Locations

Additional Notes

The Ram ProMaster uses two distinct bulb types across its model years for the license plate position: the 12961 and the DE3423.
The DE3423 is an ANSI-standardized festoon bulb recognized across the US and Canadian markets, operating at 12 volts. It uses end-cap contacts and has a 41mm length, which determines physical fitment within the license plate housing.
The 12961 is a Philips part number designation for a T10 miniature wedge bulb. It uses a W2.1x9.5d base and is rated at 12 volts and 5 watts.
The wedge base of the 12961 and the end-cap festoon design of the DE3423 are mechanically incompatible socket types, meaning the two bulbs are not interchangeable with each other.
The Ram ProMaster (2014-2018) uses the DE3423 festoon bulb for the license plate position across five consecutive model years.
The 2021 Ram ProMaster departs from the festoon format, specifying the T10 wedge-base 12961 instead.
The festoon format of the DE3423 is a common automotive bulb category in which the bulb bridges two end contacts within a cylindrical housing, rather than inserting into a socket from one end as a wedge bulb does.
The T10 designation of the 12961 refers to a tubular bulb with a nominal width of 10 thirty-seconds of an inch, a standard sizing convention in miniature automotive lighting.