The Schneider Electric A9F45170 is a 1-pole Acti9 iC60N miniature circuit-breaker rated 0.5 A with a D-curve, meaning the magnetic trip fires at 12 x In (6 A) ±20 % — sized for loads with a high inrush, like small transformers or solenoid valves, where a C-curve would nuisance-trip on startup. The 50 kA Icu at 240 V AC (EN/IEC 60947-2) is the interrupting capacity under fault; the 6 kA Icn (EN/IEC 60898-1) is the domestic-rated breaking capacity. The thermal-magnetic trip unit handles overloads (thermal bimetal) and short-circuits (magnetic coil) in one package.
Snaps onto a DIN rail (clip-on mounting,) — standard for any distribution board or sub-panel. The 18 mm width and 85 mm height mean it fits alongside other Acti9 devices on the same rail; the toggle actuator and trip indicator are visible through a transparent cover or door. Terminals accept 1–25 mm² rigid or 1–16 mm² flexible, with a 14 mm strip length and 2 N·m torque. The separate earth-leakage block means you add a Vigi iC60 module downstream if ground-fault protection is needed.