The Schneider Electric A9N1P25BGN is a 1-pole miniature circuit breaker from the Acti9 xC60 range, rated 25 A with a B-curve trip characteristic. It clips onto a standard 35 mm DIN rail and occupies 2 x 9 mm pitches (18 mm wide), so it slots into any distribution board without surprises.
Rated 25 A with a B-curve — magnetic trip between 3 and 5 times In — so it's sized for residential and light commercial final circuits where inrush is low (lighting, socket outlets). The 10 kA Icn breaking capacity at 240 V AC meets IS/IEC 60898-1 for branch-circuit fault clearing up to that level; above that, you need an upstream limiting device. Thermal-magnetic trip unit handles overloads via the bimetal strip and short-circuits via the solenoid — no electronics to fail, no auxiliary supply needed. Rated operational voltage is 220...240 V AC 50/60 Hz, so it's a straight swap for any 1P 25 A B-curve MCB on a single-phase line. IP20 means finger-safe terminals but no protection against dripping water — keep it inside the enclosure.
Tunnel-type terminals accept up to 25 mm² rigid or 16 mm² flexible; strip 13 mm and torque to 2 N·m. Toggle control with ON/OFF indication gives clear visual status without a multimeter.