They also had breastplates like breastplates of iron, and the sound of their wings was like the roar of many horses and chariots rushing into battle.
KJV
And they had breastplates, as it were breastplates of iron; and the sound of their wings [was] as the sound of chariots of many horses running to battle.
ASV
And they had breastplates, as it were breastplates of iron; and the sound of their wings was as the sound of chariots, of many horses rushing to war.