The Siemens SENTRON 5SJ4106-7HG42 is a 1-pole miniature circuit breaker with a C-curve tripping characteristic, rated 10 kA breaking capacity per EN 60898 and 15 kA per IEC 60947-2 at 400 V AC. It's also rated for 60 V DC, so it can protect a DC control bus or a small battery-backed circuit.
Pollution degree 3 (conductive pollution, typical in industrial enclosures) and overvoltage category III (distribution level). IP20 with connected conductors, IP40 in the handle area — fine for a clean panel, not for washdown zones. Halogen-free and silicon-free, which matters in semiconductor fabs or clean rooms where outgassing can kill optics or contaminate wafers. Sealable — you can lock the handle position to prevent unauthorized reset.
Current production — no end-of-life notice. Standard SENTRON catalog item.