The Lexus GS450h parking light requires bulb sizes 7443NA, 7444NA, and 168 depending on the specific version. Available information covers a range from 2007 through 2018 for the specified vehicle components.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The front parking light position of the Lexus GS450h uses three distinct bulb types across its model years: the 7444NA, 7443NA, and 168.
The 7444NA and 7443NA are both T20 dual-filament wedge bulbs rated at 12V with a 21W/5W power split, meaning one filament handles a higher-intensity function while the other handles a lower-intensity function within the same housing.
Both the 7444NA and 7443NA feature natural amber glass, which produces an amber-colored output without the use of a separate amber lens or colored coating on the bulb socket.
The 7444NA and 7443NA share the same T20 wedge base form factor and identical voltage and wattage ratings, yet they are listed as separate part numbers and are not treated as interchangeable across all fitments in these specifications.
For the 2017-2018 model years, the 7443NA is specified only for vehicles with 2 headlamps, while the 7444NA applies to the remaining configuration, indicating that headlamp count determines which T20 bulb is correct.
The 2016 GS450h front parking light uses the 7443NA exclusively under the 2-headlamp condition, making headlamp configuration a critical compatibility factor for that year as well.
The 168 is a T10 miniature wedge bulb rated at 12V and 4.9W, a single-filament design with significantly lower wattage than the T20 bulbs used in later model years.
The 168 bulb was the specified front parking light for the 2007-2011 model years, after which the specifications transition to the higher-wattage T20 family of bulbs.
All bulb types listed, the 7444NA, 7443NA, and 168, conform to ANSI standards applicable in the United States and Canada.
The T10 and T20 designations refer to the outer width of the bulb body in millimeters multiplied by two, meaning the T10 is 10mm wide and the T20 is 20mm wide, making the two form factors physically incompatible with each other in the same socket.