The Siemens 5SL6650-7BB is a 3+N-pole miniature circuit breaker rated 400 V with a 6 kA breaking capacity, C-curve trip characteristic, and 50 A current rating. This is the Italy-specific version of the standard 5SL6 series MCB.
The 3+N-pole configuration (3 poles protected, neutral switched but not protected) is common for three-phase final subcircuits in European-style panels.
Integration note
Snap-on DIN rail mounting for standard 35 mm rail. The 3+N module occupies 4 module widths (72 mm at 18 mm per pole). Rated for use in Siemens ALPHA, SIVACON, and third-party distribution boards.