What the ratings mean for fit
The 2CDS273103R0164: The Icu of 25 kA at 440 V tells you this breaker clears a hard short without welding contacts — it's the fault current it can interrupt once. The Icn of 10 kA is the service rating for repeated operation: your supply-side SCCR needs to stay below that for the panel's fault-withstand rating. Overvoltage category III means it's rated for fixed-installation distribution boards, not for socket-outlet circuits. The IP20 front and IP40 housing keep dust out of the enclosure but don't rely on it wet. Terminal torque spec of 2.8 Nm — standard for this class. Use a torque screwdriver on the cylinder-lift terminals; overtightening strips the clamp.