The lubrication units belonging to ZG series are complete systems to produce the oil+air mixture, obtained dosing small amonut of oil in a continuous flow of air. The Oil+air mixer is not provided with electronic monitoring.. The unit is controlled by a PLC which adjust the quantity of lubricant delivered; the controlling elements communicate with PLC programmable unit, which is linked to the central unit of the machine the unit is mounted on. The management software also contains a specific option to use also GMN spindles (prelubrication).