Note: While the pack works on all models, the "Permanent Patch" aspect is most critical for PSP 3000, Go, and Street models, as these cannot normally run permanent CFW without Infinity.
Sony’s final official firmware update for the PSP was version 6.61. While most older mods focused on 6.60, 6.61 offers the latest PSN (PlayStation Network) compatibility and the most up-to-date security keys. The in the pack name signifies that this pack is built specifically for the 6.61 firmware. psp 661 infinity 20 cfw pack by mrmario2011 exclusive