The Omron EE-SX672 is a through-beam optical slot sensor with a fixed 5 mm gap, designed for flag or paddle detection in compact mechanisms — think end-of-travel sensing on a pick-and-place axis or part-present verification on a conveyor. It runs on a 5 V supply and switches an NPN open-collector output, sinking up to 12 mA. The 1 ms response time is fast enough for edge counting at moderate line speeds but not for high-rate encoder replacement. Chassis-mount package, ships in bag.
The 5 mm sensing distance is the through-beam gap between emitter and receiver. A metal flag or plastic vane passing through that slot breaks the beam and toggles the output. That's a tight window — fine for small parts or registration marks, not for wide-gap applications. If your flag is thicker than 5 mm or you need clearance for debris, this isn't the sensor.
Rated for -25°C to 55°C ambient — that's indoor industrial or light commercial, not a freezer or an oven door. No IP rating in the listing, so keep it inside a cabinet or at least out of direct washdown spray.