The spot diameter for Through-beam and Retro-reflective Models is 5 mm (a typical example at 3 m), making it possible to detect small workpieces at long distances. The sensing distance for Retro-reflective Models is 15 m (when an E39-R1 Reflector is used). This is the longest leeway in the industry. The maximum ambient operating temperature is 55° with an IP67 degree of protection, allowing the Sensor to be used in severe operating environments.