The Siemens 3VA1163-3EE42-0AA0-ZD00 is a 4-pole IEC frame 160 molded case circuit breaker rated at 63 A continuous, with a breaking capacity of 25 kA at 415 V (class N). It uses a TM220 thermal-magnetic trip unit — the thermal element provides adjustable overload protection from 44 A to 63 A, while the magnetic instantaneous pickup is fixed at 10× In (630 A). The neutral conductor is unprotected, which is standard for line-side protection on a 3-phase + N system where you want phase-only overcurrent tripping.
The 160 A frame gives you physical room for larger cable lugs and a higher SCCR than a 63 A frame would. The nut keeper kit (included per the order code suffix) is a small detail that saves time on the line — no dropped hardware when torquing down the DC Power OEM termination in China.