KIDDE analogue linear smoke detector, aritech ir transmitter/receiver barrier, ir radiation reflected by prism/mirror analysed for smoke, suitable for high-level or hard-to-access installations (maximum height 25 m), powered from the same loop. no external power required, 50 m ir. 2e/1s relay 2 a 24 v. coverage 50 x 15 m, easy alignment, adjustment and testing. reduction of false alarms