Small light barriers, W9, WL9L-3P3432, 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: cable with M12 connector, 4-pin, 120 mm, light transmitter: laser, setting: teach-in button, laser class: 1, communication interface: -