The PSP Custom Firmware 6.61-Pro-C2 will work on all PSP models from the original PSP to the PSP Go and even the E1000, all you need is to be running the official 6.60 or 6.61 firmware to install and use this custom firmware.Custom Firmware PRO-B9 for 6.20, 6.35, 6.39 and 6.60 released Here it is folks! From homebrew devs Coldbird, Virtuous Flame (aka Liquidzigong) and the rest of Team Pro comes the long awaited update of their Pro custom firmware for the PlayStation Portable.