Marchal Bulb, 45 Watt, 12 Volt
This is a 12 Volt bulb with a BA21s base and axial filament (top-to-bottom rather than sideways). The BA21s base has a single contact pad at the bottom, the metal base has 3 bayonet pins. Please review the images for details.
Also available in 35 Watt, these were used in many Marchal fog-lights on early Porsche and other european automobiles.
For additional specifications, please review the item specifics.