The LX1FF450 is a replacement coil for Schneider Electric TeSys F contactors, wound for 450 V AC at 50 Hz and 550 V AC at 60 Hz. It's the part that pulls the contactor in and holds it closed — no built-in suppressor module, so you add your own RC snubber or varistor across the coil terminals if the control circuit needs one. Closing time runs 23 to 35 ms; opening is faster at 5 to 15 ms. That's typical for a frame this size — the drop-out speed matters for arc extinction on inductive loads, so the 5 ms floor is what you design around for contact separation timing.
Coil voltage limits: it drops out between 0.35 and 0.55 Uc (about 158 to 248 V at 450 V nominal), and picks up reliably between 0.85 and 1.1 Uc (383 to 495 V). That 0.35 floor is the key number — if your control supply sags below that during a motor start, the contactor drops out. The 0.85 pickup means it won't close on a weak circuit; you need nearly full voltage to pull it in. Inrush power is 550 VA at 50 Hz (650 VA at 60 Hz), dropping to 45 VA hold-in at 50 Hz (55 VA at 60 Hz). That inrush spike is what the control transformer and fuse see — size the supply for the inrush, not the hold-in. Heat dissipation runs 12 to 16 W at 50 Hz, which matters if the coil is enclosed in a small panel with other heat sources. Rated for 10 million mechanical cycles and a maximum operating rate of 2400 cycles per hour at 55 °C. That's about 40 operations per minute — fast enough for most cycling applications but not for high-speed pick-and-place.