Interstate Pneumatics 1/4″ Small Metal Air Regulator. 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.