Bugatti Veyron 16.4 Turn Signal Bulb Size

Additional Notes

• The Bugatti Veyron 16.4 front turn signal uses one of two bulb types across its production years: the 3457NA or the 3357NA, both of which are ANSI-standardized T25 wedge bulbs rated at 12 volts with natural amber glass envelopes.
• Natural amber glass in both bulb types produces an amber-colored output without the use of a painted or coated lens, which is the defining characteristic of the "NA" suffix in their designations.
• The 3457NA is a dual-filament bulb rated at 27W and 7W, meaning it carries two independent circuits within a single housing, typically serving both a higher-intensity function and a lower-intensity standby or parking function simultaneously.
• The 3357NA is a single-filament bulb rated at 27W, carrying only one active circuit, which limits its function to a single lighting role rather than the combined role of the 3457NA.
• The Bugatti Veyron 16.4 used the 3357NA for the 2006-2007 and 2010 model years, while the 3457NA was specified for the 2008-2009 and 2011-2012 model years.
• Although the 3457NA and 3357NA share the same T25 wedge base and physical housing, substituting one for the other is not straightforward, as the 3357NA lacks the second filament present in the 3457NA, making them functionally non-interchangeable in sockets wired to use both circuits.
• The T25 designation refers to the bulb's tubular form factor with a width of approximately 25 millimeters, a standard sizing classification used across many automotive applications beyond the Veyron 16.4.
• Both bulb types operate on a 12-volt electrical system, consistent with the standard automotive voltage architecture used in the Veyron 16.4.