The Lexus RC350 front turn signal uses 7440NA, 7444NA, or 7443NA bulb sizes, while the rear turn signal requires a 7440NA size. The replacement bulb chart covers 2015 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 RC350 turn signal positions are the 7440NA, 7444NA, and 7443NA. All three belong to the T20 wedge family and share the same natural amber glass construction, which produces an amber output directly from the bulb rather than relying on a colored lens.
The 7440NA is a single-filament bulb rated at 12V and 21W. Its single filament means it serves one lighting function only, making it suitable for a dedicated turn signal circuit without a secondary running light role.
The 7444NA and 7443NA are both dual-filament bulbs rated at 12V with a 21W high filament and a 5W low filament. This configuration allows one bulb to handle two separate functions, typically a turn signal and a parking or running light, within a single housing.
Although the 7444NA and 7443NA share identical voltage, wattage ratings, and T20 wedge bases, they are not confirmed as interchangeable. Differences in filament positioning between the two types can affect whether the bulb seats correctly and aligns with the intended circuit contacts in a given socket.
The Lexus RC350 front turn signal used the 7443NA for the 2015-2016 model years, then shifted to the 7444NA for 2017-2019, and later moved to the single-filament 7440NA for 2021-2022.
The rear turn signal of the RC350 uses the 7440NA across all listed model years from 2015 through 2024, with no variation in bulb type across that span.
Substituting a single-filament 7440NA in a socket designed for a dual-filament 7444NA or 7443NA would result in the loss of whichever secondary function the low-filament circuit controls, as the single-filament bulb has no low-filament contact to complete that circuit.
All three bulb types carry ANSI standardization applicable to the United States and Canada, meaning their electrical and physical specifications conform to a defined North American standard rather than a proprietary or regional specification.