From The Apple Wiki

Prototypes are Pre-Production Apple Devices. They tend to be rare and difficult to find, especially for older or newer devices or earlier stage prototypes.


Common stages for Prototypes are:

  • PROTO# (usually PROTO0-2)
  • EVT# (Usually EVT1-4)
  • EVTX (Usually EVTA-C)
  • DVT# (Usually DVT1-4)
  • DVTX (Usually DVTA-C)
  • PrePVT
  • PVT (Includes PVTe (Typically testing Devices)
  • MP (Mass production devices (usually just testing devices))

These stages are in chronological order, and this also indicates the rarity. Watch this video to learn more. Prototypes tend to have different Security Fusings than production devices, the main exception is PVT and MP, which often have production musings due to being production hardware