The Schneider Electric A9KF71303BQ is a 3-pole miniature circuit breaker from the Acti9 K60 series, rated 3 A with a C-curve trip characteristic. It breaks 10 kA Icn at 415 V AC, 50/60 Hz, per EN/IEC 60898-1. The thermal-magnetic trip unit handles the overload side; the magnetic element handles the short-circuit side.
Snaps onto a DIN rail (mounting support: DIN rail, fixed mode). Takes 6 modules of 9 mm pitch — so 54 mm wide on the rail. Height 81 mm, depth 70 mm. Tightening torque 2 N.m. Strip length 14 mm. IP20 finger-safe front. Pollution degree 2, overvoltage category II. Operating altitude 0 to 2000 m. That matters if the panel lives in a humid plant environment.
Current production — no end-of-life notice. The Acti9 K60 line is Schneider's standard MCB family; this part is a set of 4 units.