Anybody know hw to 'subdue' color that was applied a few hours ago... maybe peroxide ?

You didn't mention what color your mustache is or the color you are trying to achieve. If the color is too intense and you want to tone it down, I recommend using a product called "Just For Men Brush-In Color Gel for Mustache." It comes in 9 shades, and you only need to leave it on for five minutes. Choose a shade that's slightly darker than your current color if you want to tone it down.

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