Originally posted by duckyslinger
Also I see it says of not cfw this will not mes with jailbreak will it
No, you won't lose your jailbreak. The only way you would lose your jailbreak is if you install an official sony firmware above 3.55.
Its just a downgrader for DEX
If your console is on DEX, use the DEX downgrader
If your console is on CEX, use the rogero or rebug downgraders