Is EIP-4345 the same thing as Arrow Glacier?

I've read that the Arrow Glacier upgrade will delay the "difficulty bomb" to June 2022 – the "difficulty bomb" being the increase in the difficulty level of ETH mining. But I've read that EIP-4345 does the exact same thing. Is "Arrow Glacier" just another name for EIP-4345 or is EIP-4345 only a small part of the Arrow Glacier upgrade – Arrow Glacier making many adjustments to ETH other than just pushing back the "difficulty bomb"?