Schwarzkopf's Igora Royal Oil Developer is a conditioning, caring peroxide that's optimized to work with Igora Royal hair colors and others to maximize the coloring process. 

It comes in 4 strengths: 3% (10 vol), 6% (20 vol), 9% (30 vol) and 12% (40 vol). Use them as follows: 

- 10VOL/3% for darker or pastel coloring and for covering 100% white hair;
- 20VOL/6% for tone-on-tone coloring, white hair coverage and lightening 1-2 levels;
- 30VOL/9% for lifting 2-3 levels (3-4 levels with the Special Blondes), coloring with -00 shades and white hair coverage with the Absolutes;
- 40VOL/12% for lifting up to 5 levels and for coloring with the Fashion Lights.

Size: 1000ML