Pneumatic Pulsator is an essential component of a milking machine that controls the suction and pressure levels during the milking process. It works by producing a cyclical pulse that mimics the natural sucking motion of a calf when nursing. This rhythmic pulse is necessary to stimulate milk letdown and ensure proper milk flow from the udder. The pulsator regulates vacuum and pressure levels to ensure regular and controlled milk flow, optimizing efficiency while preventing potential udder damage due to excessive suction.