Duty cycles and switching frequency
This contactor is rated for different switching frequencies depending on the duty class: 1,000 operations per hour at AC-1 (resistive loads), 750 per hour at AC-2 and AC-3 (motor starting and running), and 250 per hour at AC-4 (plugging and inching). The AC-3e rating also lands at 750 ops/hour. That means for a conveyor motor running standard start/stop cycles, you've got headroom for frequent operation; but if you're doing reversing or jogging, you need to respect the 250/hour ceiling to avoid overheating the contacts.
That's useful when you're fitting it into a panel with odd angles or limited swing clearance.
That's handy for daisy-chaining control power without an extra terminal block. The auxiliary switch is included, with contact ratings that vary by voltage: 10 A at 24 V, 2 A at 48 V or 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, 3 A at 400 V, and 0.2 A at 440 V. Also carries a 2 hp rating at 230 V for smaller motor loads on the aux.