The Siemens 5SL4408-8 is a 4-pole miniature circuit breaker rated 400 V with a 10 kA breaking capacity and a D-trip curve at 8 A. On a 400/230 V three-phase panel, that lets you isolate the entire load with one device — common in European-style distribution boards where the neutral is switched for full isolation. At 93 x 75 x 84 mm, it occupies four modular-width slots (each pole roughly 18 mm).
RoHS compliant since June 2013. REACH candidate-list information is available on request. No UL or CSA listing appears in the record — the 5SL4 series is designed primarily for IEC markets (EN 60898) and carries CE marking for European distribution.