> 3% (10vol): From light color turn to dark color, no lightening.
> 6% (20vol): From dark color turn to light color, lightening 1-2 level.
> 9% (30vol): From dark color turn to light color, lightening 2-3 level.
> 12% (40vol):From dark color turn to light color, lightening 3-4 level.
The hydrogen peroxide composition is mild, less irritating, and it can mix fast and evenly with hair color cream.