By definition:
"Sway bars are essentially a torsion spring that is attached to a vehicle's frame, linking the left and right suspensions together. Also called anti-roll bars, stabilizer bars, or simply anti-sway bars, they reduce vehicle body roll and improve handling when cornering."
Looks like a good one but it does seem to be a little low under the differential. There might be some adjustment available to raise that section. Look for the linkage that connects the ends of the bar to see if that can be adjusted to rotate the bar up in the center.