Distance-Settable Reflective Sensor - Visible Light, 20 to 80 mm Sensing Distance - For detecting parts near a backgroundThe Distance Settable Reflective Photosensor is useful for detecting objects near a background, without detecting the background itself. The sensing distance is adjustable from a minimum of 20mm to a maximum of 80mm. The emitter light source is a red LED, which provides a visible aiming spot to aid in installation. Its a reflective sensor the emitter and receiver are in the same housing, aimed in the same direction, but angled slightly toward the