The Siemens 5SY4425-7CV is a 4-pole miniature circuit breaker (MCB) from the SENTRON 5SY4 series, rated for a breaking capacity Icu of 15 kA at 400 V AC with a C25 trip characteristic. The C-curve (5–10× In) handles moderate inrush from motor starters, small transformers, or lighting ballasts without nuisance tripping, while still protecting the 4 mm² or 6 mm² copper you'd typically run on a 25 A circuit.
Snap-on DIN rail mount, standard 4-module width (72 mm at 18 mm per pole). The 4-pole configuration covers three-phase-plus-neutral circuits common in European-style distribution boards. Terminal capacity accepts up to 25 mm² conductor for the load side; the busbar fork slots are compatible with Siemens SENTRON pin-and-fork busbar systems for panel assembly.