The Lexus RX350 front turn signal uses 7440NA, 7444NA, or 7443NA bulb sizes, while the rear turn signal requires a 7440NA size. The replacement bulb size chart covers 2007 through 2024 model years.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The three bulb types specified across the Lexus RX350 turn signal positions, the 7440NA, 7444NA, and 7443NA, all share the T20 wedge base form factor and operate on a 12V circuit, making them physically similar in housing style despite differences in filament count and wattage output.
The 7440NA is a single-filament bulb rated at 21W, while the 7444NA and 7443NA are both dual-filament bulbs rated at 21W and 5W respectively, meaning the dual-filament variants serve two lighting functions from a single bulb whereas the 7440NA serves only one.
All three bulb types carry the "NA" suffix, which denotes natural amber glass coloring under the ANSI standard applicable to the US and Canadian markets, as opposed to clear-glass variants that rely on an amber-colored lens housing to produce the required signal color.
The front turn signal position on the Lexus RX350 uses different bulb types across its model years, with the 7443NA specified for 2013-2017, the 7444NA for 2018-2019 and 2022, and the 7440NA for 2007-2012 and for 2021 and 2023-2024.
Because the front position alternates between single-filament and dual-filament bulbs across different model years, the 7440NA is not a direct drop-in replacement for the 7443NA or 7444NA, and substituting one for the other would result in a wiring or function mismatch.
The rear turn signal position uses the 7440NA single-filament bulb across all listed model years from 2007 through 2022, indicating a consistent single-function wiring configuration at that position throughout that span.
The 2019 rear turn signal entry carries a fitment note specifying the 7440NA for vehicles with single-beam headlights, indicating that headlight type is a relevant variable when selecting the correct rear turn signal bulb for that model year.
Although the 7443NA and 7444NA share identical wattage ratings of 21W/5W and the same T20 wedge base, they are distinct ANSI part numbers and are not confirmed as interchangeable within these specifications.