Omron F3SJ-A2105P20 Safety Light Curtain, 20mm Detection, 21

That 20 mm figure means it catches fingers reaching into a hazard zone — finger-protection class per IEC 61496-1 — so it suits access guarding where smaller gaps are needed, not just hand or body presence. With 140 beams spaced at 15 mm pitch, the protective height reaches 2105 mm, covering tall openings like conveyor infeed or robot cell gates. Operating range spans 0.2 m to 7.0 m, so it works in both tight machine loading stations and wider perimeter zones. The 24 VDC supply is standard for safety circuits; IP65 rating means the emitter and receiver heads withstand washdown and dust ingress — suitable for food-and-bev lines or machining coolant environments. Blanking and muting functions are built in, allowing fixed obstructions (like a fixture) to be ignored and temporary interruptions (like a pallet passing) without tripping the safety output.