The Schneider Electric A9F03363 is an Acti9 iC60N miniature circuit breaker — a 3-pole, 63 A, B-curve unit built for distribution panels. Breaking capacity is the headline here: 36 kA Icu at 12–133 V AC, 20 kA at 220–240 V, 10 kA at 380–415 V, and 6 kA at 440 V — all per EN/IEC 60947-2. That's a high-interrupting rating for a 63 A frame, meaning it can clear serious fault currents without upstream fuses or a bigger breaker having to step in. The Icn (rated short-circuit capacity) per EN/IEC 60898-1 is 10 kA at 400 V, which covers most commercial panel requirements. Thermal-magnetic trip unit, category A (no intentional short-time delay), so it's a straight distribution breaker — not for selective coordination schemes that need a delayed trip.
Snaps onto DIN rail — 6 x 9 mm pitches wide (54 mm), 91 mm tall, 78.5 mm deep. Double terminals top and bottom accept 1–35 mm² rigid or 1–25 mm² flexible, with a 3.5 N.m tightening torque and 14 mm strip length. IP20 finger-safe front, so it's panel-ready behind a closed door. The toggle gives local ON/OFF control plus a trip-indicator flag. Contact-position indicator confirms isolation status — the breaker is rated for isolation per both EN/IEC 60898-1 and EN/IEC 60947-2, so you can use it as a visible-break disconnect for downstream work.