Mercedes-Benz E250 Turn Signal Bulb Size

Additional Notes

• The 3457NA is the specified front turn signal bulb for the Mercedes-Benz E250 across the 2014-2016 model years.
• The 3457NA follows the ANSI standardization system, which is the North American bulb classification framework used in the United States and Canada.
• This bulb uses a dual-filament design, meaning it contains two separate filaments within a single housing, allowing it to serve two distinct lighting functions at different wattages.
• The two filaments operate at 27W and 7W respectively, where the higher wattage filament typically handles the active turn signal function and the lower wattage filament handles a secondary role such as parking or daytime running light duty.
• The 3457NA is built on a T25 wedge base, which is a push-in style base that does not use a bayonet or screw fitting.
• The "NA" suffix in the 3457NA designation indicates natural amber glass, meaning the amber color is produced by the glass envelope itself rather than by a clear bulb paired with an amber lens.
• The bulb operates on a 12V electrical system, consistent with standard automotive voltage.
• The natural amber glass construction of the 3457NA is a fitment consideration, as substituting a clear-glass equivalent such as the 3457 in a housing designed for a clear lens would not produce the required amber output for turn signal compliance.