The Siemens 5SL4263-6CC is a 2-pole miniature circuit breaker (MCB) rated 63 A at 400 V with a 10 kA breaking capacity, B-curve trip characteristic. It's a current-production part (lifecycle stage: active). For the panel builder: this is a DIN-rail mount unit, 2-pole wide, so it occupies two module spaces in the distribution board. The B-curve means it trips at 3–5× rated current — standard for resistive and general-purpose loads, not motor starting where inrush would nuisance-trip it.
Lifecycle is active. No end-of-life notice, no successor announced — this is the current catalog item. RoHS compliant since June 2013. REACH declares lead (CAS 7439-92-1) above the 0.1% threshold in the candidate list, so it's reportable under Article 33 but not banned. For a BOM freeze or compliance audit, the declaration pack is straightforward: no SVHC restrictions beyond the standard lead listing.
Mounts on standard 35 mm DIN rail in the panel. 2-pole form factor, so it fills two TE (module spaces). The 10 kA breaking capacity at 400 V is the fault-interrupt rating per IEC 60898 — enough for most commercial and light industrial sub-distribution boards. On the van: if you're swapping a failed 63 A B-curve 2-pole in a lighting or general-power panel, this is the direct Siemens part number.