Miniature light barriers, W4S-3, WTB4S-3P3161, switching distance max.: 4 mm ... 180 mm, sensor principle: reflection light sensor, detection principle: background suppression, switching output: PNP, switching type: light switching, connection type: cable with plug M8, 3-pin, 100 mm, light transmitter: PinPoint LED, setting: potentiometer, communication interface: -