The FE 10‑RL‑PS‑K4 is a through‑beam laser sensor from the F10 series, designed for precise object detection over long distances. It consists of a transmitter and receiver pair that must be aligned for operation and supports a maximum sensing distance of 4,000 mm (4 m) with a switching frequency up to 4,000 Hz, making it suitable for fast processes. It uses a red laser (Class 1) as its light source and offers a PNP output configuration with a 4‑wire cable (2 m) connection. The operating voltage ranges from 10 V to 30 V DC, and the device is protected to IP67 standards for dust and water ingress. It can operate in ambient temperatures from –20 °C to +50 °C, and the unit includes a Teach‑in adjustment for easier setup.