Arrow Pneumatics full line of Filters, Regulators and Lubricators are proudly Made in the USA. In-Line Air pressure regulators are used to reduce and maintain pressure at a level suitable for the device downstream. Pneumatic equipment operating at a higher than recommended pressure can cause excess torque, force and wear while simultaneously wasting compressed air. Pneumatic equipment operating below specified pressure can cause machines to fail to meet their design performance specifications. Precise pressure control is essential for efficient operation of air-powered equipment. An air line regulator is a control valve which reduces the upstream air supply pressure level to a specified constant downstream pressure. Installation, operation & maintenance instructions are included with each Arrow unit.