The Mercedes-Benz E350 parking light utilizes bulb sizes 12961 and 2357NA for illumination. Data for the specified lighting components covers the range from 2006 through 2012.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 12961 is the dominant bulb type across the Mercedes-Benz E350 front parking light specifications, appearing consistently from 2006 through 2014.
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 T10 wedge base is a push-in fitment with no locking mechanism, meaning the bulb is retained solely by the tension of the socket housing.
The 2357NA is an ANSI-standard dual-filament bulb with a BAY15d bayonet base, rated at 12V with a 26.9W high filament and an 8W low filament, and features natural amber glass rather than a clear envelope.
The BAY15d base on the 2357NA uses an offset pin arrangement to prevent incorrect installation, as the two filaments serve distinct functions and must align with the correct circuit contacts.
The 2357NA and 12961 use entirely different base types, a bayonet versus a wedge, making them physically non-interchangeable without a socket adapter.
For the Mercedes-Benz E350, the 2357NA fitment is specific to the 2006 model year front parking light, while the 12961 applies to the 2007-2014 model years.
Model years 2007-2012 carry a conditional 12961 fitment noted specifically for vehicles equipped with halogen capsule headlamps, indicating that headlamp type is a relevant variable in socket compatibility for those years.
The 5W rating of the 12961 places it in the low-wattage category typical of parking and position lights, which are designed for continuous illumination without generating significant heat load on surrounding trim components.
The natural amber glass of the 2357NA produces its color through the glass coating itself rather than through a colored lens, a construction detail that affects how the bulb behaves if the lens housing is clear or lightly tinted.