The SICK LFP0400-A4NMB is a Type 4 safety light curtain from SICK's deTec4 Core series. It is designed for perimeter access guarding and area protection around hazardous machinery. This device creates a vertical screen of infrared light beams between an emitter and a receiver. If any beam is interrupted, it sends a stop signal to the machine's safety control system to prevent access to the danger zone.