The Schneider Electric A9K23220 is a 20 A, 2-pole miniature circuit breaker from the Acti9 iK60N series, curve B, rated to break 6 kA at 400 V AC per EN/IEC 60898-1.
Snaps onto a standard DIN rail — 36 mm wide (2 modules at 18 mm each), 85 mm tall, 78.5 mm deep. Tighten to 2 N·m. The toggle gives local ON/OFF indication, and there's a padlocking provision for lockout/tagout.
