Download Link File: http://gomyshare.com/Irvingmyra9656547/iPod_Touch Read the whole description. iPhone 3GS 4.0.1 Custom Firmware Download: (Not Hacktivated) (For AT&T users) In order to downgrade to 3.1.2 you are going to need a shsh blob and need your host file modified and this program called tinyumbrella which you be able to download here: http://gomyshare.com/Irvingmyra48996964/JAILBREAK