Freightliner Sprinter front and rear side marker bulbs utilize 12961, 3457NA, and 12821 bulb sizes across different positions on the vehicle. The replacement chart covers 2002 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.
The Freightliner Sprinter front side marker position uses the 12961 bulb across the 2010-2021 model years, with the 2019-2021 entries specifying this fitment applies to vehicles equipped with halogen capsule headlamps.
The 12961 is a Philips miniature wedge bulb in the T10 form factor, rated at 12V and 5W, with a W2.1x9.5d base.
Front side marker positions on the 2002-2006 Sprinter use the 3457NA bulb, an ANSI-standard dual-filament wedge in the T25 form factor with natural amber glass, rated at 12V and 27W/7W across its two filaments.
The rear side marker position on the 2010-2018 Sprinter also uses the 12961 bulb, sharing the same T10 wedge format and W2.1x9.5d base as the front side marker fitment on the same generation.
The rear side marker position on the 2007-2009 Sprinter uses the 12821, also a Philips T10 miniature wedge bulb with a W2.1x9.5d base, rated at 12V and 5W.
Although the 12961 and 12821 share the same base type, voltage, wattage, and T10 form factor, they carry distinct Philips part numbers and are listed separately in the specifications, indicating they are not treated as interchangeable within these fitment records.
The 3457NA carries a significantly higher wattage than the 12961, with a 27W primary filament compared to 5W, reflecting a fundamentally different bulb category that is not cross-compatible with the T10 wedge positions.