The Mercedes-Benz S550 parking light requires a bulb size of 12961 for the lighting system. Available information covers the specific time range from 2007 through 2013.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Mercedes-Benz S550 front parking light uses the 12961 bulb across the 2007-2013 model years.
The 12961 is a Philips part number designating a miniature wedge bulb in the T10 form factor.
T10 bulbs are among the most widely used miniature bulbs in automotive lighting, commonly found in parking lights, courtesy lights, and instrument panel applications.
The 12961 operates at 12 volts and draws 5 watts, which is typical for low-intensity position and parking light functions.
The base type on the 12961 is W2.1x9.5d, a wedge-style base that relies on the tension of the socket contacts rather than a twist-lock or bayonet mechanism to hold the bulb in place.
The W2.1x9.5d base designation is standardized, meaning the 12961 is physically interchangeable with other T10 wedge bulbs sharing that base type, provided voltage and wattage ratings are also compatible.
Because the same bulb size is specified for every listed model year of the S550, a single replacement bulb type covers the full 2007-2013 front parking light application without variation.