Schwarzkopf's new Oil Developer is a conditioning, caring peroxide that's optimised to work with Igora.
It comes in 4 strengths:
3% (10 vol) for darker or pastel colouring and for covering 100% white hair;
6% (20 vol) for tone-on-tone colouring, white hair coverage and lightening 1–2 levels;
9% (30 vol) for lifting 2–3 levels (3–4 levels with the Special Blondes), colouring with -00 shades and white hair coverage with the Absolutes;
12% (40 vol) for lifting up to 5 levels and for colouring with the Fashion Lights.