This Turck inductive proximity sensor is manufactured with a nonshielded coil, designated by "Ni" in the part number. Nonembeddable (nonshielded) units require a metal free area around the sensing face. Because of possible interference of the electromagnetic fields generated by the oscillators, minimum spacing is required between adjacent or opposing sensors. It is good engineering practice to mount sensors horizontally or with the sensing face looking down. Avoid sensors that look up wherever possible, especially if metal filings and chips are present.
It's rated operating distance is 8 mm and the "M12" section of the part number means the sensor is partially threaded and the housing diameter is 12 mm. The "ADZ32X" means the sensor is normally open, uses 2-wire AC/DC, (power MOSFET output), needs 20-250 VAC, 10-300 VDC 400 mA and has 1 LED. Lastly, the "B3131" means this Turck sensor has a straight microfast (1/2") connector, with 3 pins and standard wiring.