1006503B Hengst Electronic Switching Element (R928028409, WE-1SP-M12X1)1006503B Hengst Electronic Switching Element (R928028409, WE 1SP M12X1); 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