What this MCB covers
The Siemens 5SL6601-7BB is a miniature circuit breaker rated 400 V with a 6 kA breaking capacity, configured as 3+N-pole, C-curve, 1 A, in the Italy version.
The 3+N-pole format covers three phases and neutral in one module width per pole — check the total width against your enclosure rail budget. Rated for 400 V line-to-line, so it suits three-phase 400/230 V networks common in European industrial and commercial installations. The C-curve characteristic is the default choice for general-purpose motor circuits and lighting in panels where the inrush isn't extreme.