The ABB S201-B13NA is a 1P+N miniature circuit breaker with a B-curve trip characteristic rated at 13 A, 480Y/277 V. For motor or transformer starts that draw higher inrush, a C- or D-curve would be the better fit; this one is sized for lighting, heating, and general-purpose receptacle circuits.
For a BOM-freeze or a panel-builder stocking the S200 series, this part is still the standard catalog choice.
The 1P+N configuration switches the line conductor and provides a switched neutral — the neutral pole opens and closes with the line pole but does not have overcurrent protection. This is common for single-phase final circuits where disconnecting both poles is required by local code (e.g., for socket-outlet circuits in some jurisdictions). Rated 480Y/277 V — the Y indicates a wye system where the phase-to-neutral voltage is 277 V and the phase-to-phase voltage is 480 V. This MCB is designed for 277/480 V wye distribution, not for 240 V split-phase or 208Y/120 V without checking the voltage rating against the system.