The Siemens 5SL4213-7 is a SENTRON miniature circuit breaker, 2-pole, C-curve, rated 13 A at 400 V AC with a 10 kA breaking capacity per both EN 60898 and IEC 60947-2. That 10 kA rating means it can safely interrupt a fault current up to 10,000 A without welding contacts or cascading upstream — the standard for residential and light commercial distribution boards.
The C-curve trips between 5 and 10 times rated current, so the 13 A rating holds motor inrush and transformer energization without nuisance trips — a common choice for general-purpose branch circuits. At 40 °C ambient the breaker derates to 12.01 A; at 55 °C it's 10.35 A, so factor that into panel thermal calculations if the enclosure runs hot.
Snap-on DIN rail mount, 2 modular width units (36 mm wide), 76 mm deep, 90 mm tall.