[Avodah] Retzuos that are Black on Both Sides

[Chesky Salomon via Avodah]

On Wed, Apr 15, 2015 at 11:34 AM, Micha Berger wrote:
> There was a bachur next to me this morning whose retzu'os were painted
> black on both sides. And I believe I know why this is done, in case
> a retzu'ah gets flipped. Or perhaps to be chosheish for the Rambam's
> description of such retzu'os being "noi".

I've only ever heard of the leather being soaked in dye; and the
reason given was not for flipped retzu'os but for scratches: if the
entire thickness of the strap has been dyed, a scratch will not expose
undyed leather. (This does not address your actual question, though)

—Chesky Salomon