Interstate Pneumatics 1/4″ economy metal compact design mainly used as a replacement on small portable compressors. WR1120 Series Regulator come with One Gauge Port. These are Stamped to indicate Air Flow Direction. You must choose correct part # for your application. Pneumatic equipment that operates at higher than recommended pressure can cause damage, failure, create a safety hazard and can waste compressed air. That is why regulators are highly recommended as they reduce the upstream pressure to a specified constant downstream pressure and ensures that the compressed air stays within a specified pressure range. This unit regulates air pressure of the air line to prevent damage. It has the advantage of stable pressure, high precision, quick reaction & firm lockup. It can be freely combined with other air source treatment products.