The Lexus ES300h back up light requires a 921 bulb size for proper installation and function within the rear lighting assembly. Available information covers the range from 2013 to 2018 for the specified vehicle and component.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 921 bulb is the sole bulb size specified across all back up light positions on the Lexus ES300h for the 2013-2018 model years.
The 921 is a wedge-type bulb, classified under the T15 designation, which refers to its tubular glass envelope size expressed in eighths of an inch.
The 921 operates at 12 volts and 16 watts, placing it in the mid-range of standard automotive incandescent wedge bulbs by wattage.
The 921 conforms to ANSI standards applicable in the United States and Canada, meaning it meets a defined set of electrical and physical tolerances for those markets.
The wedge base design of the 921 requires no separate metal base or socket pins, as the glass pinch at the bulb's base serves as the electrical contact and retention mechanism.
Several inner back up light entries for the Lexus ES300h carry a "Japan Product Part" notation, specifically for the 2013, 2014, and 2016 model years, indicating those particular assemblies were sourced from Japanese-market components.
The outer and inner back up light positions share the same 921 bulb size across all listed years, which means a single bulb type services both positions on this vehicle.
Because the Japan Product Part designation applies only to select inner back up light entries and not to all years uniformly, fitment context may differ between model years even when the bulb size remains identical.