1000525B Hengst Mechanical / Optical Maintenance Indicator (R901025312, WO-D01-2,2-M-160); Maintenance indicators facilitate the monitoring of filters by signaling when there is an excessive pressure differential and/or back pressure in the filter.

Features: Modular design; Mechanical/visual indicators (WO) with a single switching point and memory function; Electronic switching element (WE) with one or two switching points; Capability to suppress signals during cold starts; Optional enhanced resistance offered through stainless steel differential pressure indicators.