The 81525101 is a pneumatic air flow regulator designed for sub-base mounting in modular pneumatic timer systems. It features a free flow capacity of 30 NL/min with an adjustable orifice diameter ranging from 0 to 0.5 mm, enabling precise control of air flow rates in pneumatic circuits. The regulator is mounted on a sub-base platform that accommodates multiple modular elements connected via instant push-in connections for semi-rigid tubing with outer diameter 4 mm. This component is commonly used in pneumatic automation systems where controlled air flow is essential for timing and actuation functions, providing reliable and repeatable performance in industrial control applications.