The phrase represents a dying art in smartphone modding: low-level, dangerous, partition-based unlocking. While modern devices (Pixel, OnePlus) allow simple fastboot flashing unlock , the Sony Xperia Z5 Premium remains a fortress due to its Trim Area security.
The device must be turned off, then connected to the PC while holding the Volume Down button to enter "Flashmode" (indicated by a green LED). Wiping Data: Within Flashtool, you must select the e6833 lock remove ftf hot