Mercedes-Benz C350e high beam and low beam headlight bulbs both use H7 size. The replacement chart covers 2016 to 2018 production years with bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Mercedes-Benz C350e uses the H7 bulb type across all listed model years for both high beam and low beam headlight positions, making it the sole bulb type present in these specifications.
The H7 is a single-filament halogen bulb operating at 55 watts with a PX26d base, a standardized two-pin connector design widely used in European vehicle lighting systems.
The H7 bulb produces light through a tungsten filament enclosed in a halogen gas-filled quartz envelope, which allows the filament to burn hotter and brighter than a standard incandescent bulb while maintaining a compact form factor.
For the Mercedes-Benz C350e, the H7 specification applies to model years 2016-2018 without variation across that range for either beam position.
The use of the same H7 bulb size for both high beam and low beam positions means the vehicle does not use a dual-filament bulb such as the H4, instead relying on separate single-filament units for each function.
H7 bulbs are not universally interchangeable with other common halogen types such as H1, H3, or H11, as each designation corresponds to a distinct base configuration and physical form that prevents cross-fitting without modification.
The PX26d base of the H7 is keyed, meaning it can only be seated in one orientation within the headlight housing, which is a design feature intended to ensure correct filament positioning relative to the reflector or projector optics.
Substituting an H7 bulb with a physically similar but electrically incompatible type risks misalignment of the light output pattern, which affects both road illumination and oncoming traffic glare.