The contactor uses spring-loaded terminals for both the main current circuit and the auxiliary/control circuit, accepting 2x (0.25 to 2.5 mm²) solid or stranded wire.
The 12 A rating per NO/NC contact is the continuous thermal current (Ith) — the contactor can carry 12 A continuously without exceeding temperature rise limits. This is the figure to match against your load current, not a switching rating. For DC switching of auxiliary contacts, the ratings drop significantly with voltage: 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, 0.3 A at 220 V, and 0.8 A at 440 V. The minimum DC switching capability is 0.01 A at 24 V — below that, the contacts may not reliably break the arc. The coil pickup is guaranteed at 85% of rated voltage (20.4 V for a 24 V coil) and dropout at 110% (26.4 V), so a sagging 24 V bus below 20.4 V will cause the contactor to drop out.
It occupies a 45 mm width, 60 mm height, and 72 mm depth — a compact S00 footprint.