Schwarzkopf Professional Oil Developer is a conditioning, caring peroxide thats optimized to work with new Igoral Royal but which can also be used with old-style Igoraif you still have some tubes to use up.
It comes in 4 strengths : 3% (10 vol), 6% (20 vol), 9% (30 vol) and 12% (40 vol). Use them as follows:-
3% for darker or pastel colouring and for covering 100% white hair
6% for tone-on-tone colouring, white hair coverage and lightening 12 levels
9% for lifting 23 levels (34 levels with the Special Blondes), colouring with -00 shades and white hair coverage with the Absolutes
12% for lifting up to 5 levels and for colouring with the Fashion Lights