The A3L4AA-6L8G is an Allen-Bradley A3 series pilot light: a 480V transformer-type indicator with a green LED. It is a panel-mount component for status indication on motor control centers or distribution panels, drawing its illumination from the line voltage through an integral step-down transformer rather than a separate supply.
Mounts in a standard 30 mm panel cutout. The 480 V primary winding connects directly across two phases; the secondary drives the LED at low voltage. No external ballast or dropping resistor is needed. Verify the transformer VA rating against the inrush of the LED circuit — the integral design handles it, but a multi-gang installation sharing one transformer would need a separate unit per lamp.