That means it holds its full 250 A rating in a warm panel, which is the spec that matters when you're stacking breakers in a crowded enclosure. Three-pole design, configured for line protection — the standard role for a main or feeder breaker in a distribution panel. Breaking capacity hits 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.
That saves panel space and wiring time — no separate accessory kit to order and snap on.
That 110 mm depth is the key number for enclosure selection — it dictates the minimum cabinet depth for the breaker plus wiring space behind it.