All Azbil’s Model HPX-AG_ _ Digital Fiber Optic Switches share basic features, including 4-element LED and APC for stable light emission, superior timer functions, and five selectable sensing modes for high accuracy detection as well as model-specific features such as remote tuning, alarm output, dual output, active zone, differential setting, databank, and synchronous external input models. The dual display shows the incoming light level and present value side by side..