The Schneider Electric A9F03320 is an Acti9 iC60N miniature circuit-breaker — a 3-pole, 20 A thermal-magnetic breaker with a B-curve trip characteristic. It's designed for distribution duty in commercial and industrial panels, protecting branch circuits against overloads and short circuits.
This breaker carries a 36 kA Icu at 12-133 V AC, 20 kA Icu at 220-240 V AC, and 10 kA Icu at 380-415 V AC per EN/IEC 60947-2. The 6 kA Icn at 400 V per EN/IEC 60898-1 is the domestic-grade rating; the higher 60947-2 figures are what you rely on for industrial coordination studies.
Depth is 78.5 mm, height 91 mm. That 78.5 mm depth is what you check against gland-plate clearance in a shallow enclosure; it's the dimension that trips people up when swapping into a tight retrofit can. Terminals accept 1-25 mm² rigid or 1-16 mm² flexible, with a 2 N·m tightening torque and 14 mm strip length. Double terminals top and bottom let you daisy-chain feed-through without a separate distribution block.
Dual-certified to both EN/IEC 60898-1 (domestic MCB standard) and EN/IEC 60947-2 (industrial switchgear standard). That dual footprint matters when the same panel feeds both a utility-metered supply and a machine tool — one breaker covers both compliance regimes. Pollution degree 3, overvoltage category IV, suitability for isolation marked on the nameplate. IP20 finger-safe terminals.