The 440R-W23218 is a monitoring safety relay (MSR320P) with 1 NC, 2 NC, and 3 NC safety mat/light curtain inputs, featuring 2 PNP auxiliary outputs and removable terminals. It operates on 24 VDC supply, designed for DIN rail mounting, and is rated for Category 4 safety applications. Note: Original manufacturer warranty does not apply, but includes Radwell's 2-year warranty.