Signal integrity note
The E2B-M18KN16-M1-B2: This is the unshielded 18 mm barrel inductive sensor from Omron's E2B series, set for a 16 mm sensing range with a PNP normally closed output and an M12 connector. The 16 mm reach is generous for an 18 mm unshielded sensor — expect the field to extend past the barrel face by a few millimetres radially, so plan for metal beside or behind the target to avoid false triggers. Unshielded means no internal ferrite band; you get longer range but less immunity to stray metal and EMI. If you've got a VFD or contactor within a few inches of the sensing path, verify the signal on a scope before trusting the feedback to your PLC.
Brass barrel with metric 18 mm thread, short body — fits a standard 18 mm hole in a bracket or through a gland plate. Use a locknut to secure it. PNP normally closed output; source current to the load when no target is present. Verify your PLC input sinks the sensor's rated output current and the M12 connector mates with off-the-shelf cordsets. Since it's unshielded, keep the cable away from high-current power cables; if you must run it in parallel, leave adequate separation or use separate metallic trunking.
If you have a BOM line that needs a second source, look for an 18 mm unshielded PNP NC sensor with the same 16 mm nominal range and M12 connector; the Omron E2E series is a common alternative but check pinout and barrel length.