It's designed for AC circuits and carries a 6 kA breaking capacity per EN 60898, with a 5 kA rating per UL 1077 and CSA C22.2 No. 235.
The 3 A rating at 35 °C is the headline number, but you need to watch the derating: at 40 °C it's good for 2.82 A, at 45 °C it's 2.73 A, at 50 °C it's 2.63 A, and at 55 °C it's 2.53 A. That's enough for most secondary distribution panels downstream of a larger feeder breaker. The UL 1077 rating at 5 kA covers North American installations where the breaker is used as a supplementary protector. The installation depth is 70 mm, and the overall depth is 76 mm, so factor that into your enclosure depth when you're laying out the gland plate.
The design complies with IEC 81346-2 and DIN EN 61346-2, function designation F (protective device). Vibration resistance per IEC 60068-2-6 covers ±1 mm at 5 to 25 Hz and 50 m/s² at 25 to 150 Hz — it'll hold up on a machine base or a conveyor drive panel.