You need E3 flasher, and an USB dongle to get to FSM ( ex : E3 card reader )
Be careful, you don't want to end up buying a clone, Check the e3-tech distributors list.
There are two packages 1. E3 flasher limited edition which includes e3 flasher, e-sata hdd station and screwdrivers.
2. just the e3 flasher itself.
You don't need e-sata station, because you can downrgade your console without it.