Backlash is the mask Dusty Hayes wears as driver of Gator, and the power is a lash of energy that repels what is thrown at him. The fan wiki says it can even turn aside Vanessa Warfield’s Whip, and adds that it creates sound waves as well. In Counter-Clockwise Caper he wears it while driving Rhino.
It is a first-season regular. The fan wiki lists it from The Deathstone onward, and in The Book of Power it is Backlash that gets Dusty out of the sand trap in the lost city of Mong Paco. Wikipedia’s list calls it a kinetic blast.
Kenner packed the mask with Gator in 1985 and with Afterburner in 1987, where Wikipedia says it is called New Backlash and makes a holographic clone, though our toy record for Afterburner lists just a Backlash Mask. The Vacuum mask that goes with Billboard Blast is the same sculpt in another color, according to the fan wiki.
