The Omron D4GS-N2R is a slim-profile safety door switch with two normally-closed slow-action contacts (2NC). It's designed for interlocking guard doors on machinery where panel space is tight — the slim body fits where a standard safety switch won't. The horizontal key insertion (R-type) means the actuator enters from the side, which suits sliding or hinged guards where vertical access is blocked.
The conventional free-air thermal current (Ith) is 2.5 A per EN60947-5-1. That's the continuous current the contacts can carry in free air without exceeding temperature rise limits — it's your sizing figure for the control circuit load, not a switching rating. For a safety circuit feeding a PLC input or a safety relay, 2.5 A is ample; just make sure the upstream protection coordinates with the 100 A withstand.