The lubrication units belonging to ZGX series are complete systems to produce the air-oil mixture, obtained dosing small amount of oil in a continuous flow of air. The unit is controlled by a PLC which adjust the quantity of lubricant delivered; the delivery of the air-oil mixture is monitored by optical sensors to the outlets of the mixer. The controlling elements communicate with PLC programmable unit, which is linked to the central unit of the machine the unit is mounted on. The unit is assembled inside a metallic box, and has got filters both on the air line and on the oil line; it has been designed for lubrication of spindle as “plug & play” accessory.