Capacitive sensors for object detection have a linear electric field. They detect solid objects such as wafers, circuit boards, cardboard boxes, stacks of paper, bottles, plastic blocks and plates as well as liquids through container walls or pipes made of glass and plastic (max. thickness 4 mm). M30, capacitive sensor, M30x1.5, cable, normally open/closed (NO/NC), PNP, 20 mm, flush