Lexus ES350 Turn Signal Bulb Size

Additional Notes

• The 7440NA, 7443NA, and 7444NA bulbs are the three types specified across the Lexus ES350 turn signal positions. All three are ANSI-standard T20 wedge bulbs rated at 12 volts with natural amber glass, making them amber-producing without the need for a colored lens or housing filter.
• The key distinction between the 7440NA and the 7443NA/7444NA lies in filament count. The 7440NA is a single-filament bulb rated at 21W, while the 7443NA and 7444NA are dual-filament bulbs rated at 21W/5W, meaning they serve both a high-intensity turn signal function and a lower-intensity secondary function such as parking or daytime running light.
• The 7443NA and 7444NA share the same T20 wedge base type and voltage rating, but they are not interchangeable. The two types differ in pin configuration, and installing the incorrect type risks improper fitment or electrical contact failure.
• The front turn signal on the Lexus ES350 (2007-2011) uses the 7440NA, a single-filament bulb. Starting with the 2012 model year, the front position shifted to dual-filament types, with the 7444NA and 7443NA appearing across subsequent years.
• The 2019-2020 front turn signal specifications note a "With LED Headlamps" condition for the 7444NA fitment, indicating that the bulb requirement for those years is tied to a specific headlamp configuration.
• The rear turn signal across the 2007-2018 model years uses the 7440NA exclusively, a single-filament 21W wedge bulb, reflecting a consistent rear lighting design across that span.
• The natural amber glass construction of the NA-suffix bulbs is a defining characteristic. Unlike clear-glass equivalents, the amber tint is built into the glass envelope itself, producing a compliant amber signal output independent of the lens color.
• The 7443NA and 7444NA are both dual-filament T20 wedge bulbs with identical voltage and wattage ratings, yet their internal pin offsets differ. This offset is a deliberate design feature that prevents a dual-filament bulb from being seated in a socket intended for a single-filament 7440NA.