These pressure regulators are designed for precise regulation of air pressure in pipes, vessels, and process lines. Regulators maintain constant pressure by providing high accuracy, precision control, and maximum stability under the most adverse conditions. Regulators feature high-accuracy pressure regulation up to ±0.1%, a servo-operated control mechanism for pressure stability, and start-up stability that returns to output setting after a long down-time. Locking nut prevents inadvertant adjustment of pressure. Unit can be in-line or panel mounted.