It is useful for all hydraulic circuits. Addition of this colouring additive to an hydraulic oil gives it a blue colour. Don’t use blue concentrate for aqueous solutions: the proportions may change, according to the requirement from 0.02 to 0.1% in the hydraulic oil. These features allowr: the avoidance of a confusion with motor oil, a quicker detection of possible leakages, an easy identification of the lubricant and an easy reading of the lubricant gauge level.