Ian Zachary 30 VolumeDeveloper is the desired volume lightening 2-3 levels for highlights with high-lift shades, or highlighting with the Ian Zachary Blue Powder Bleach.
Ian Zachary 20 VolumeDeveloper is used to deposit pigment at the same level, or one to two levels lighter. 20 VolumeDeveloper is the best volume to use with Permanent Cream Hair Color to achieve excellent gray hair coverage.