With the ultrasonic barriers of the ARK series, each consisting of a transmitter and receiver unit measuring 30 mm × 20 mm × 12 mm, the supplier EGE offers a reliable, robust option for detecting objects in harsh environmental conditions. The devices achieve switching frequencies of up to 150 Hz and a range of up to 300 mm. Typical applications include the detection of transparent objects or objects that are difficult to detect optically, such as counting or checking the presence of bottles. The advantages of the ultrasonic principle come into play particularly in applications that are unfavourable for optical sensors - typically environments in which strong reflections or dust, steam and smoke cause restricted visibility. The sensors, made of PBTB, are designed for a temperature range between -15 and +60 °C and, thanks to protection class IP 67, function reliably even in demanding industrial environments.