The S3 frame size tells you the physical envelope: 70 mm wide, 140 mm tall, 152 mm deep. That depth is the dimension you need to check against your enclosure depth — at 152 mm, it's a mid-depth contactor that fits most 200 mm+ deep cabinets but may be tight in shallow wall-mount boxes. Wire termination is screw-type on the coil and main contacts. The main circuit accepts solid conductors from 2.5 to 16 mm² and stranded from 6 to 70 mm². That covers most motor feeder sizes up to about 30 kW at 400 V. The coil terminals take smaller wire: 2x (0.5 to 1.5 mm²) solid or stranded, or 2x (0.75 to 2.5 mm²). The storage range is wider — that's the shipping and shelf-life limit, not the running condition.
The contactor includes an auxiliary switch, so you don't need a separate add-on block for basic status feedback. That's the minimum air gap to adjacent metalwork or other devices for heat dissipation and arc containment.