It's a 4-pole unit rated 400 A continuous at 40 °C, with an adjustable thermal-magnetic trip range from 600 A minimum to 4000 A maximum — so you set the pickup to match your downstream load, not the other way around. The interrupting ratings climb with voltage: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 7.5 kA at 690 V. The basic switch core is order code 3VA2340-5JQ42-0AA0, meaning the -0JH0 suffix adds the shunt trip and the specific aux contact arrangement.
Above that it derates linearly: 375 A at 55 °C, 350 A at 60 °C, 325 A at 65 °C, and 300 A at 70 °C. Maximum power loss is 96 W at rated current. That's the heat you need to vent from the enclosure; for a 4-pole breaker at 400 A, it's modest enough for a standard ventilated panel but worth checking if you're packing multiple breakers in a sealed box.
That's a 4-pole frame size — wider than a 3-pole equivalent by roughly one pole pitch. The storage limit governs shipping and warehouse conditions, not running duty — if it sat in an unheated warehouse at -30 °C, it's fine to install once warmed above -25 °C.