The Schneider Electric A9K23616 is an Acti9 iK60N miniature circuit breaker rated 16 A at 30 °C, curve B, 1P+N configuration. The thermal-magnetic trip unit gives a magnetic threshold of 3 to 5 x In, so it clears short-circuit faults fast while tolerating inrush from resistive loads like heaters or lighting banks.
Depth is 78.5 mm, height 85 mm — the 78.5 mm depth matters when the gland plate or enclosure lid clearance is tight; a 100 mm deep enclosure leaves roughly 21.5 mm for wiring behind the breaker. Single terminal per pole top and bottom keeps daisy-chaining straightforward.
IP20 finger-safe terminals suit enclosed distribution boards; not rated for wet or dusty environments.