That C-curve means it holds steady through inrush up to 5–10× rated current and trips magnetically beyond that — the right choice for moderate motor starts, transformer inrush, or mixed resistive-inductive loads in a control panel. The 1.6 A rating is at 35 °C ambient; derate it to 1.54 A at 40 °C, 1.5 A at 45 °C, and so on down to 1.4 A at 60 °C, so if your panel runs hot, size up accordingly.
Width is 54 mm, which is 3 modular units (MW) on a standard DIN rail. Mounting position any, so you can orient it vertically or horizontally in a tight gland plate layout. Combined terminal top and bottom — that's a time-saver for the wireman: one screw captures both the incoming busbar and the outgoing conductor. Fastening method is the quick-assembly system (snap-on DIN rail), and it's sealable (padlockable handle) for lockout/tagout compliance.