Its 4.5 kA breaking capacity is certified per EN 60898, which covers residential and light commercial branch-circuit protection. The 1+N design switches both line and neutral, with the neutral pole opening after the line pole — a detail that matters for single-phase final subcircuits where an isolated neutral is required for isolation.
The C-curve characteristic means the magnetic trip activates at 5 to 10 times rated current (100–200 A for this 20 A unit). That suits loads with moderate inrush — lighting banks, small motors, control transformers — where a B-curve would nuisance-trip on startup but a D-curve would delay too long for fault clearing. In a panel with a higher available fault current (e.g., close to a transformer), you would need a 6 kA or 10 kA rated unit such as the 5SY6020-7KL. Per the datasheet, the breaker is rated for 10 000 mechanical switching cycles — a figure that reflects the expected endurance under normal load switching, not fault interruption.
The neutral conductor switching function is built in, so no separate neutral bar is required downstream for the protected circuit. The supply cord position is any, which simplifies busbar routing on either the top or bottom feed.