Searching for "ps4 tool downgrade v1 00 install" leads you to sketchy forums, YouTube videos with fake download links, and paid "software" that claims to revert any PS4 to 1.00. These are almost always scams or malware. Why? Because:
A: Impossible. PS4 Pros shipped with firmware 4.05 minimum. You cannot downgrade below that. ps4 tool downgrade v1 00 install
If you own a launch-day PS4 (CUH-10xx / CUH-11xx) that was never updated past firmware 3.55, you might be able to downgrade to 1.00. But it requires a hardware tool, not a software executable. Searching for "ps4 tool downgrade v1 00 install"