You might check out the Wikipedia Cigarette lighter receptacle
page, which explains that there are two slightly different sizes (I assume you would want the slightly bigger of the two). There's also a somwhat common socket which is significantly smaller, and frequently associated with BMW, defined by the ISO 4165
standard... you presumably don't want that in a trailer here.
1979 Boler B1700RGH, pulled by 2004 Toyota Sienna LE 2WD
Information is good. Lack of information is not so good, but misinformation is much worse. Check facts, and apply common sense liberally.
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