Nuclear Weapons
noun
Nucleus arms (へいき), aka weapons, are nuclear weapons.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
核兵器を使用する前に、説明書に書かれている操作方法を必ずお読みください。
Before using the nuclear weapon, please carefully review the instruction booklet.