The D4NL1AFAB is a safety-door lock switch from the Omron D4NL series, built to guard access on machinery with a mechanical key lock and a 2NO/2NC contact configuration. The screw terminals are standard for panel wiring; no special crimp tool needed, just a screwdriver and a ferrule if the wire is stranded.
The 2NO/2NC contact set gives you two normally-open safety channels and two normally-closed monitoring channels — enough for a dual-channel safety circuit with feedback loop, which is common on guarded machine access points. Switching capacity is 3 A at 240 V AC and 270 mA at 250 V DC, so it handles control-level loads (relays, PLC inputs, contactor coils) but not motor power directly — the contacts are sized for the safety circuit, not the main power. Mechanical life is rated at 1 million cycles; electrical life at 500,000 cycles — that is a long service interval for a door switch on a production line that cycles a few times per shift. The four head directions let you orient the key entry top, bottom, left, or right, which helps fit the switch to the door hinge side and the guard frame without extra brackets.