Three power poles, all normally open, with one auxiliary NO contact built in.
AC-3 at 16 A tells you this contactor is sized for a motor load up to roughly 7.5 kW at 400 V — the standard induction motor starting current (6–8× FLC) is what AC-3 covers. The AC-4 category also listed means it's rated for plugging and inching duty, so it handles the occasional reverse-on-the-fly without derating. The coil is 400...415 V AC, which is common in European 400 V three-phase panels; if your control voltage is 230 V or 24 V DC, this coil won't pick up.
Integration notes
The preassembled reversing busbar means the two contactor halves are mechanically interlocked and the power bus is already linked; you just land the incoming line and outgoing motor leads. Flame retardance meets UL 94 V1 and NF F 16-101/102, which is typical for rail and industrial control panels.