The Chromatic Applicator is a block in Galacticraft that allows you to color vacuum glass, lighting panels, and other paintable objects. When opened, it has two slots, an arrow with a block on top, and three buttons that say "Mix Color" "Apply Paint" and "Reset Color". When you put a dye in the left slot and press "Mix Color" the block in the middle will slowly start to change into the dye's color. And, in theory, when you put a vacuum glass or anything else in the right slot when the square is colored to your preference and press "Apply Paint", it will color the object. Unfortunately, the block does not currently work.