The OSI-RE-SS is a reflector- sort linear optical beam smoke detector built to work as a element of hearth alarm devices. The beam operates totally on the basic principle of light obscuration utilising an Infra-Red beam. OSI-R-SS is actually a 4-wire conventional reflector-type linear optical beam smoke detector to be https://www.firesense.co.uk/type/conventional-fire-system/conventional-beam-detectors/