yes 1 off is a part made by a person and not produced. So there is only 1 and even if copied most of the time wouldn't be 100% the same. Like my oil pressure gauge bracket.I started with a piece of stainless steel and made it so it was 1 of a kind. I made one for Wendys bike so it is actually 2 of a kind now. Or Wendys sprocket cover is 1 of a kind. Stock cover smoothed and polished the engraved with a tribal rose then to finish it the petal area is a pewter rose. That is custom. Your signals would be not custom made but custom mounted so again custom in my opinion. It involved drilling and shimming not just bolted on.

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