This listing is for a replacement slot-type photomicrosensor compatible with the EE-SX677-WR family. The sensor uses a through-beam 5 mm slot to reliably detect small opaque objects and typically supports detectable objects of about 2 × 0.8 mm or larger. It provides an NPN open-collector output with selectable Dark-ON/Light-ON operation to suit common control wiring. The WR designation denotes a pre-wired cable version in supplier documentation; confirm the exact cable length and pinout with the seller before installation. Reference documents also report an operating voltage range of 5-24 VDC and built-in output protection features; verify specifics against the component datasheet when replacing critical parts.