The REL-IR4/LDP-110DC/4X21 is a plug-in industrial relay with power contacts designed for robust switching operations. It operates with a nominal coil voltage of 110V DC and provides four AgNi changeover contacts. This relay is capable of handling a maximum switching voltage of 250V AC/DC and a limiting continuous current of 6A. For enhanced usability and diagnostics, it is equipped with a manual test button, a yellow status LED, a freewheeling diode for coil protection, and a mechanical switching position indicator. With a high mechanical service life of approximately 20 million cycles and a wide operating temperature range, this relay is suitable for demanding applications in industrial control and automation systems.