Three poles, line-protection design, with an undervoltage release (UVR) built in. Breaking capacity hits 242 kA at 240 V, 187 kA at 415/440 V, and still 121 kA at 500 V; at 690 V it drops to 7.5 kA, so keep that in mind for 690 V bus work.
Deployment context
This is a panel-mount MCCB — 138 mm wide, 248 mm tall, 110 mm deep — sized for standard distribution boards and motor control centers. The 250 A frame covers feeder and large branch circuits where you need a high interrupting rating without stepping up to a bigger frame.
The undervoltage release (UVR) means it will trip if control voltage drops — common for safety disconnects or emergency-stop chains. Power loss maxes at 40 W, so ventilation in the enclosure matters if you're grouping several breakers.