This bulb holder is used in most VW models up to the mid 70's that have Duplo lights with a 45t-41 socket. If you're not sure which Duplo bulb we're talking about, take a look in the options tab where the bulb is listed.
This bulb holder not only attaches the high and low beam bulb, but also attaches and connects the daytime running lights. To connect the headlight, a special plug is needed, if you don't have one, you can also find it in the options tab.
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