KJV : And <2532> they had <2192> (5707) breastplates <2382>, as it were <5613> breastplates <2382> of iron <4603>; and <2532> the sound <5456> of their <846> wings <4420> [was] as <5613> the sound <5456> of chariots <716> of many <4183> horses <2462> running <5143> (5723) to <1519> battle <4171>.
NASB : They had breastplates like breastplates of iron; and the sound of their wings was like the sound of chariots, of many horses rushing to battle.
NASB# : They had<2192> breastplates<2382> like<5613> breastplates<2382> of iron<4603>; and the sound<5456> of their wings<4420> was like<5613> the sound<5456> of chariots<716>, of many<4183> horses<2462> rushing<5143> to battle<4171>.