The 3UG3207-2B: The two-pole bow electrode detects conductive liquid levels by completing a circuit between the two poles when the liquid bridges them. Lateral installation means the probe mounts through the side wall of a tank, not the top — important for retrofitting existing vessels without overhead access. The reference code K per IEC 81346-2 classifies it as a monitoring/measuring device in the panel schematic, which affects how it's labeled in your BOM and wiring diagrams.
The substance prohibitance date of 05/01/2012 indicates compliance with RoHS and REACH restrictions as of that date — the part does not contain restricted substances above the thresholds that took effect then. No UL or IEC certification is explicitly listed in the spec record, but as a Siemens SIRIUS component it carries CE marking and is designed to relevant IEC standards for industrial level probes.