Ceiling mount IR wireless detector. 6m opening cone base at 2,10m height installation, 8m opening cone base at 3m height installation. 54 zones over 6 concentric cone sectors. Operating range 80m in open field. 9V alkaline battery provided. Compatible with HELIOS and VILLEGGIO, HALENTE and HALLEY RX-TX wireless units, RIVERRF concentrator, TRHPLUS telephone dialler.