Miniature light barriers, W4SL-3, WL4SL-3P2232, switching distance max.: 0 m ... 12 m, sensor principle: reflection light barrier, detection principle: autocollimation, switching output: PNP, switching type: light/dark switching, connection type: connector M8, 4-pin, light transmitter: laser, setting: teach-in button, laser class: 1, communication interface: -