This device is mostly used for a measurement of length of a tool by CNC machines.

The sensor has sensitive optical, triggered by pressing a sensor surface.

Power supply	5-24V
Switch type	NC – normally closed = output is active, when sensor is NOT triggered. — or — NO – normally openned = output active, when sensor is triggered.
Output type	NPN – switch to GND — or — PNP – switch to power supply
Cable length	1m, 2m or 4m