Mercedes-Benz CL550 License Plate Bulb Size

The Mercedes-Benz CL550 license plate light requires a 12961 bulb size for proper installation and function within the rear exterior lighting assembly. Available data for the specified vehicle covers the range from 2007 through 2014.

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
2007-2014	12961

Bulb Specifications

Description	Bulb Size
Philips part number. Miniature wedge bulb (T10) with W2.1x9.5d base. 12V, 5W.	12961

Other Locations

Additional Notes

The Mercedes-Benz CL550 uses the 12961 bulb for the license plate position across the 2007-2014 model years.
The 12961 is a Philips part number designating a miniature wedge bulb in the T10 form factor, which is one of the most widely used bulb types in automotive auxiliary lighting positions such as license plate, parking, and side marker applications.
The T10 designation refers to the bulb's tubular shape, with the number indicating a width of roughly 10 millimeters across the envelope.
The base type is W2.1x9.5d, a wedge-style base that relies on the tension of the socket contacts rather than a bayonet or screw mechanism to maintain the electrical connection.
The bulb operates at 12 volts and 5 watts, which is consistent with standard low-current auxiliary circuits found in passenger vehicle electrical systems.
The T10 wedge format is shared across a large number of vehicle makes and models, though fitment into a specific socket housing depends on the physical dimensions of that housing, not the bulb type alone.
The 12961 designation is specific to Philips and may correspond to equivalent bulbs sold under different part numbers by other manufacturers, provided the base type, voltage, and wattage ratings match.
Because the same bulb size applies uniformly to all eight listed model years of the CL550, no variation in socket type or electrical specification is indicated across that production span.