Miniature light barriers, W4S-3 Glass, WLG4S-3F2234, switching distance max.: 0.01 m ... 5 m, sensor principle: reflection light barrier, detection principle: autocollimation, switching output: PNP, switching type: dark switching, connection type: connector M8, 4-pin, light transmitter: PinPoint LED, setting: cable, teach-in button, communication interface: -