Bulb Sizing for W123 Aftermarket Head Lamp (Feituo)

[BlueGermanTank]

I recently bought aftermarket lamps to put on my 1985 300 D. However, the vendor is a third-party, and the original manufacturer, a Chinese outfit called “Changzhou Feituo“ (no relation to another called Ningbo Feituo), doesn’t have any real contacts besides an unresponsive Alibaba sales rep. The build quality is surprisingly nice, they have milk bottle heavy glass covers, and otherwise seem to fit the car well.

Has anyone here ever used these before? The high/low beam is a standard H4, but the socket for the fog lights is a small square opening. If I rounded it out with a drill or dremel, my H4 Amber lights would fit, but I’m wondering if this is made for a specific size before I start making changes. None of the three auto parts stores I brought it to recognized this socket. It is connected to a single red positive wire and ground (as expected for foglights).


EDIT: SAME AS THE EUROSPEC, MY MISTAKE.

[vwnate1]

? Maybe a link to where you bought those ? .

Peach Parts right here sells nifty yellow fog lamp bulbs afforedably, they've been in my 1982 240D some years now .