The Lexus RX400h uses a 7440NA bulb size for both front and rear turn signal applications. The replacement chart covers 2006 through 2008 model years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 7440NA is the sole bulb type specified for the Lexus RX400h across all listed turn signal positions and model years.
The 7440NA follows the ANSI standard, meaning it conforms to the electrical and dimensional specifications established for the North American market, covering the United States and Canada.
This bulb uses a single-filament design, which means it serves one lighting function only, as opposed to dual-filament bulbs that handle two functions such as braking and signaling from a single unit.
The T20 wedge base is the mounting type for the 7440NA, a configuration where the bulb is held in place by the socket walls rather than a bayonet or screw base.
The natural amber glass of the 7440NA produces its amber signal color directly through the glass envelope rather than relying on a colored lens housing to filter a clear bulb.
The 7440NA operates at 12 volts and 21 watts, which are standard values for automotive turn signal applications on 12V vehicle electrical systems.
The same 7440NA specification applies to both the front and rear turn signal positions on the RX400h for the 2006-2008 model years, indicating interchangeability between those positions.
Because the 7440NA carries natural amber glass, substituting a clear 7440 bulb in its place would alter the output color unless the housing lens itself is amber-tinted.