Mercedes-Benz E350 Turn Signal Bulb Size

Additional Notes

• The Mercedes-Benz E350 front turn signal specifications cover model years 2006-2016 and reference three distinct bulb types: 3457NA, 3357NA, and 2357NA.
• The 3457NA is the most frequently specified bulb across this range, appearing in seven of the eleven model years listed.
• All three bulb types carry the "NA" suffix, which denotes natural amber glass. This coloring produces the amber turn signal output directly from the bulb itself rather than relying on a colored lens.
• The 3457NA and 3357NA are both T25 wedge-base bulbs operating at 12V, yet they differ in filament count. The 3457NA is a dual-filament bulb rated at 27W/7W, while the 3357NA is a single-filament bulb rated at 27W only.
• Because the 3457NA and 3357NA share the same T25 wedge base and housing size, physical fitment between the two is possible, but substituting a single-filament 3357NA where a dual-filament 3457NA is specified would result in the loss of the secondary filament function.
• The 2357NA, specified for the 2006-2007 Mercedes-Benz E350, uses a BAY15d bayonet base rather than a wedge base, making it physically incompatible with the T25 socket used in later model years.
• The 2357NA operates at 12V with a dual-filament output of 26.9W/8W, placing its high-filament wattage marginally below the 27W high filament of the 3457NA.
• For model years 2008-2012, the front turn signal specifications include the qualifier "With Halogen Capsule Headlamps," indicating that the listed bulb size applies specifically to vehicles equipped with that headlamp configuration.
• The 3357NA single-filament bulb is specified for the 2012 and 2014 model years, while the surrounding years in the same range call for the dual-filament 3457NA, reflecting a non-continuous pattern in filament type across the lineup.
• All three bulb types conform to ANSI standards applicable in both the United States and Canada, classifying them as standardized replacements within the North American market.