The F3SG-4RA0320-14 by Omron is a photoelectric switch and safety light curtain. It can detect the presence of objects in a range of up to 45 meters and is used for safety systems that need to detect the presence of people or objects. It features a double-beam optical system that is composed of a transmitter and receiver. This system creates a blocked beam when something or someone passes through it. The F3SG-4RA0320-14 is an IP67 rated device, meaning it is dust tight and can be safely submerged in up to 1 meter of water for up to 30 minutes. It is also UL approved and has a range of other features such as wide light receiving area, high-speed response time, anti-interference (high-frequency noise and fluorescent lights), adjustable LED indicator, and a short-circuit protection output.