Igora Developers are professional hair developer lotions by Schwarzkopf Professional, used to mix with Igora permanent and demi-permanent hair colors (like Igora Royal, Vibrance, or Royal Absolutes) to activate the color, providing lift, intensity, shine, and long-lasting results. They come in various strengths (10, 20, 30, 40 Volume/3%, 6%, 9%, 12%) and forms (oil-based for richness, liquid/gel activators for Vibrance), offering different levels of lift and application flexibility for stylists.