Twice as vigilant. High-frequency corridor sensor Presence Control PRO DUAL HF DALI for indoors, ideal for passageways and long corridors, installation height up to 3.5 m, with digital DALI interface for controlling 2 lighting channels, DUAL-HF technology for radial detection of 20 m in two directions, detection regardless of temperature, HF-sensor technology also detects movement through glass, wood and stud walls, switches light ON_ almost instantly.