The Omron EE-SX670 is a through-beam slot-type optical sensor with a 5 mm sensing gap. It switches an NPN open-collector output at 5 V supply, making it a direct-fit part for flag detection, edge counting, or home-position sensing inside machinery enclosures where the ambient temperature stays between -25°C and 55°C. The 1 ms response time handles moderate-speed object pass-through but won't catch fast encoder edges.
Chassis-mount package with a 5 mm slot — bolt it to a bracket or plate with the flag passing through the gap. The NPN open-collector output needs a pull-up resistor to the MCU or PLC input rail; 5 V supply is fixed, so no wide-range regulator needed. The 1 ms response means the output pulse width is at least 1 ms for a flag moving through the slot — factor that into your controller scan cycle or interrupt latency. Keep the wiring short and shielded if running more than a meter to avoid noise coupling into the collector line.