What it is:
Blond Studio 9 Oil Developer 20 and 30 Volume is oil-enriched to enhance the overall performance of the 9-level lightener.

What it does:
  The oil is responsible for boosting the lift and keeping the lightener result predictable. It is our way to achieve up to 9 levels of lift, quicker, with lower volume developers.

What else you need to know:
The oil-base in the developer also offers optimal mixing and application due to its creamy consistency.

Loreal Professionel Blond Studio Oil Developer - 33.8 oz