The 1SNA645001R0300, also known as RB121-24VUC, is a screw terminal interface relay from the R600 series. It operates with a rated control supply voltage of 24V AC/DC and features a single SPDT output contact for versatile switching. The output is rated for 5-250V AC and can handle currents from 60mA up to 6A. This model includes an integrated LED for status indication and, with its compact 6mm width, is well-suited for applications in space-constrained industrial control panels and automation systems.