It's a 3-pole unit rated at 20 A continuous at 40 °C, and it holds that rating up to 55 °C before it starts to derate — at 70 °C it's still good for 19 A. The interrupting capacity is the headline number here: 75.6 kA at 240 V AC, 52.5 kA at 415 V, 32 kA at 440 V, and it still holds 7.5 kA all the way up to 690 V. The UVR means the breaker trips if control voltage drops — common in safety circuits or remote-shutdown schemes. The auxiliary switches let you feed status back to a PLC or indication lamp without adding external relays.
The 76.2 mm width (3 inches) is the same as many other 3-pole SENTRON breakers in the 3VA family, so swapping between ratings in the same panel slot is straightforward. Maximum power loss is 14.5 W.
In a panel fed from a transformer with high available fault current, that number determines whether this breaker can be the main or a downstream device. The thermal-magnetic trip curve (not specified here, but standard for the 3VA line) handles overloads and short circuits. The trip indicator on the front tells you whether it tripped on overload or fault, which saves troubleshooting time on a down line.