The Siemens 5SJ6308-7 is a 3-pole miniature circuit breaker from the SENTRON 5SJ6 series, rated at 8 A with a C-trip characteristic and a 6 kA breaking capacity per both EN 60898 and IEC 60947-2 at 400 V AC.
The sealable feature (Yes) means the terminals can be locked or sealed after commissioning, useful for installations where tamper-proofing is required by site policy or insurance.
Halogen-free and silicon-free construction, so it's suitable for clean environments where outgassing could contaminate optics or contacts. Vibration resistance tested to 50 m/s² at 25–150 Hz and 60 m/s² at 10–150 Hz per IEC 60068-2-6 — holds up in industrial panels near rotating machinery.