1965 Dodge Dart Charger

Because there are intensity ratio requirements for the bright (brake or turn) and dim (tail or park) functions, and with some kinds of lamp designs the optics are efficient enough that a 3-candlepower dim filament makes the dim function too bright and not enough difference between it and the bright function, hence the bulb with the 2-candlepower dim filament. We really oughtta be talking about this in another thread; this is getting pretty far afield of Ulf's build…