The SENTRON 3VA1340-1AA42-0AB0 is a 4-pole switch disconnector on the IEC frame 400, rated at 400 A continuous. It's a straight disconnect — no overload or short-circuit protection built in, just a manual load-break switch for isolating a circuit under load or for maintenance lockout. The nut keeper kit on both sides of the main current circuit means the busbar or cable lugs get a positive mechanical clamp that won't back off under vibration; that's a detail you appreciate when you're torquing connections in a tight panel and can't get a second wrench on the back nut. No trip unit, no electronics; this is a copper-and-steel disconnect that relies on the upstream breaker or fuse for fault clearing.
This is a 4-pole unit on the 3VA1 IEC frame 400, so it's sized for main incomer or large subfeed duty in a distribution board. The nut keeper kit on both sides of the main circuit connection means you can land incoming and outgoing conductors without needing to hold a nut on the blind side — a real time-saver when you're building a panel on the bench or swapping it in the field. Mounts on a standard mounting plate; no DIN-rail clip on this frame size, so plan for bolt-down with the supplied keeper hardware.