The Siemens 5SJ6115-7 is a 1-pole SENTRON miniature circuit breaker from the 5SJ6 family, rated 1.6 A with a C-curve tripping characteristic.
Wire range accepts solid and stranded conductors from 0.75 to 25 mm² — that covers most panel wiring from 1.5 mm² lighting tails up to 6 mm² feeder tails without needing a reducer. The terminals are sealable, so you can lock the cover after commissioning to prevent tampering in a metered or security installation. Ambient temperature range is -20 to +45 °C, with a derating curve above 40 °C; storage range is wider at -40 to +75 °C, which matters if the panel sits in an unheated warehouse before energizing. Mechanical service life is 20 000 switching cycles — that's typical for an MCB used as a disconnecting means rather than a daily-operating switch.
Installation depth is 70 mm — shallow enough that it clears most enclosure gland plates without a spacer.