The Schneider Electric A9P55610 is a miniature circuit-breaker (MCB) from the Acti9 iC40H range, built for distribution panels. That 5...10 x In magnetic tripping limit is what differentiates a C-curve from a B or D — it's the sweet spot for circuits where the startup surge won't hit a B-curve's lower threshold but doesn't need a D-curve's wide band for heavy inductive loads.
Clips onto a DIN rail (EN/IEC 60898-1 mounting support) and takes up 2 x 9 mm pitches — so 18 mm wide, 85 mm tall, 74 mm deep. That's a single-module width in a standard 18 mm-per-pole grid. Terminals are tunnel-type, top and bottom, accepting 1 to 10 mm² flexible or 1 to 16 mm² rigid wire.
If you're holding a BOM freeze and need documentation, the part carries suitability for isolation (yes) and a contact position indicator — both useful for lockout/tagout procedures. The 20000-cycle electrical and mechanical durability is typical for this class; it's not a daily-switch application, but it'll handle routine breaker operations over the panel's service life.