The OSI-RE-SS is a reflector- style linear optical beam smoke detector intended to operate to be a element of fireplace alarm programs. The beam operates primarily on the theory of light obscuration utilising an Infra-Purple beam. OSI-R-SS is really a four-wire conventional reflector-kind linear optical beam smoke detector to be https://www.firesense.co.uk/type/conventional-fire-system/conventional-beam-detectors/