The ColorMelter coloring tool from Schwarzkopf Professional allows the blending of up to three colors in a single step.
The coloring tool consists of a melting palette and melting sponge. With it, colorists fill the melting palette chambers with colors, pick them up with the sponge, and apply them to the hair in one stroke,omitting any hard lines and visible transitions.
Watch how to create an ombre with the ColorMelter:
See how its used for a fashion color creation: