The Siemens 5TT5051-0 is a SENTRON Insta contactor with 3 normally-open and 1 normally-closed contact, rated for 63 A at 400 V AC and actuated by a 230 V AC coil (220 V DC also accepted).
The 230 V AC coil means it pulls in on a standard control voltage; the 220 V DC acceptance gives flexibility if you're running a DC control bus. Three NO contacts and one NC give you three power legs plus a feedback or interlock circuit without adding aux blocks. Stack them tight without airflow and you'll derate or trip early. Supplementary devices can be installed on this contactor (auxiliary contact blocks, surge suppressors, etc.), so you can expand its function without swapping the base unit.