Mercedes-Benz SLK300 front fog lights use H7 and 9006 bulb sizes, while rear fog lights require P21W bulbs. The replacement chart covers 2009 to 2011 production 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 Mercedes-Benz SLK300 front fog light uses two different bulb types across the 2009-2011 model years, with the H7 fitted to 2010-2011 vehicles and the 9006 fitted to the 2009 model year.
The H7 is an ECE-standardized single-filament halogen bulb rated at 12V and 55W, mounted on a PX26d base. Although it originates from European and worldwide regulatory frameworks, it also holds approval in the US and Japan.
The 9006 is an ANSI-standardized single-filament halogen bulb rated at 12V and 55W, mounted on a P22d base. Its standardization falls under US and Canadian regulatory frameworks.
Despite sharing identical voltage and wattage ratings of 12V and 55W, the H7 and 9006 use physically different bases, the PX26d and P22d respectively, making them non-interchangeable in the SLK300 front fog light housing.
The rear fog light on the SLK300 uses the P21W bulb across all three model years, 2009-2011, without variation.
The P21W is an ECE-standardized single-filament signalling bulb rated at 12V and 21W, mounted on a BA15s bayonet base. Its 21W output is notably lower than the 55W rating of the front fog light bulbs.
The BA15s bayonet base of the P21W is a single-contact fitting, which is a relevant distinction when sourcing a replacement, as the visually similar BA15d base carries dual contacts and is not compatible.