I recently tried it on a few different leather straps, imho he leather that works best is something that dresses it down, light brown/beige.... Dressing it up with dress straps took away from the overall look.
I tried with the mottled faded underside of a leather nato & it looked great!
But the nato wouldnt buckle upside down & it was only 20mm... Got to have 21mm.
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