On Thu, 15 Oct 2020 09:32:20 +0200, Thomas Prufer
wrote:

On Wed, 14 Oct 2020 20:05:06 +0100, T i m wrote:

This is why I was unsure if there was a formal designation for this
base and wiring (two connections, one filament and not using the metal
of the cap as a (ground) connector).

B15d is bayonet, 15 mm, double
B15s is bayonet, 15 mm, single

Ah, thanks for the explanation Thomas. ;-)

(t triple, q uadruple, , p penta/five)

;-)

A is for automotive, Y yellow (though this rule seems often ignored).

Ok.

And BAY15d may have different-height pins, with two base contacts and case for
ground, for double-filament automotive lights that need a single mounting
orientation (brake & running light, I think is one...)

Understood. As mentioned in my OP, the pins aren't offset (in either
orientation) but I don't know if there is also a height standard /
range for the non-offset pins?

At least that gives me a bit more info to search for options.

Cheers, T i m