Mercedes-Benz Sprinter Roof Marker Bulb Size

The Mercedes-Benz Sprinter roof marker bulb uses a 12821 size specification for this component. The replacement chart covers vehicle production years spanning 2022 to 2025.

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
2022-2025	12821

Bulb Specifications

Description	Bulb Size
Philips part number. Miniature wedge bulb (T10) with W2.1x9.5d base. 12V, 5W.	12821

Other Locations

Additional Notes

The Mercedes-Benz Sprinter uses the 12821 bulb for its roof marker lights across the 2022-2025 model years.
The 12821 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 marker and courtesy lighting applications.
The T10 bulb operates at 12 volts and draws 5 watts, placing it in the low-wattage category typical of marker and position lighting rather than primary illumination.
The W2.1x9.5d base type is a wedge-style connector, meaning the bulb is held in place by tension from the socket rather than by a bayonet or screw mechanism.
The W2.1x9.5d base designation refers to a specific wedge base standard where 2.1 millimeters is the wire contact width and 9.5 millimeters is the base length, which determines physical socket compatibility.
Because the 12821 uses a standardized T10 wedge base, it shares physical fitment with many other T10-designated bulbs, though wattage and voltage ratings must match the original specification to avoid electrical or thermal issues.