The 3RT2337-1AP60: The AC coil (screw-type terminals) means you need a clean AC control supply at the panel — no DC conversion to worry about on the line side. Coil type is AC, so verify your control transformer taps before wiring.
Mounting and fit
Handy when you're cramming gear into a tight enclosure or retrofitting an old panel where the rail isn't perfectly square.
What it can handle
The -40 °C low end matters if the line sits in a cold plant over a weekend shutdown. Wire termination accepts 2× (0.5...1.5 mm²) solid or 2× (0.75...2.5 mm²) stranded — standard control wiring sizes. No special ferrules needed for the stranded side, but a ferrule makes a cleaner connection in vibration-heavy spots like conveyor drives.