The 480 VAC rating (with a 600 VAC frame) means it handles standard 480Y/277 V and 600 V industrial distribution voltages; the 3-pole construction suits three-phase systems (delta or wye) where all phases need coordinated overcurrent protection.
Panel-mounted — no DIN-rail adapter. The XT4 frame uses a fixed rear-panel mounting pattern; the front flat terminals accept bus bar or cable lugs. For a panel-builder, that means the breaker occupies a dedicated cutout or sub-panel, not a DIN rail slot alongside contactors and relays. Verify the mounting hole pattern against the existing panel layout before committing the BOM.