Siemens 5SL6113-6BB MCB, 1-pole B 13A, 6kA

The Siemens 5SL6113-6BB is a 1-pole B-curve miniature circuit breaker rated at 13 A for 230/400 V AC systems with a 6 kA breaking capacity. The 6 kA short-circuit capacity covers most commercial and light industrial distribution boards fed by a typical 100–250 kVA transformer; if your fault current exceeds that, you'd step up to the 10 kA or 15 kA variant in the same 5SL6 family.