The Siemens 5SJ6316-7RC is a 3-pole miniature circuit breaker from the Retail line, rated 16 A with a C characteristic and a 6 kA breaking capacity. The 6 kA breaking capacity tells you it can safely interrupt a fault current up to 6,000 A at the rated voltage; that's sufficient for most residential and light commercial panelboards, but if your available fault current at the panel exceeds 6 kA, you'll need a higher-rated breaker upstream for coordination.
Its 3-pole form factor occupies three modular-width positions (about 54 mm total). The C-curve thermal-magnetic trip mechanism requires no external power; it's self-powered from the line side. Keep the busbar finger-protection covers in place after wiring — the 6 kA interrupt rating assumes proper arc-quenching clearance inside the enclosure.