The MGN60878 is a Schneider Electric C60N miniature circuit-breaker from the Multi9 range — a 2-pole, C-curve unit rated 4 A at 50 °C per EN/IEC 60947-2. The C-curve magnetic trip at 8.5 x In (±20%) handles motor inrush and transformer energization without nuisance tripping, but still clears fast on a hard short.
The 20 kA Icu at 240 V AC drops to 10 kA at 415 V and 6 kA at 440 V — that's the standard derating for higher system voltages. For a 240 V delta or line-to-line circuit, that's enough headroom for most commercial panels. At 415/440 V, the 6–10 kA range still covers typical industrial distribution, but check your available fault current before committing.
IP20 rated, so it's for enclosed panels only — no washdown exposure. The toggle gives local ON/OFF indication, and the contact position indicator confirms isolation status per EN/IEC 60947-2.