The OSI-RE-SS is usually a reflector- variety linear optical beam smoke detector made to run to be a element of hearth alarm methods. The beam operates totally on the basic principle of light obscuration utilising an Infra-Crimson beam. Close/span> You can't obtain this webpage as this item is not really https://www.firesense.co.uk/type/conventional-fire-system/conventional-beam-detectors/