Type 12

Type 39 was a type of TARDIS used by Time Lords. It was a much older model than the Type 40 used by the Doctor. Professor Chronotis owned a Type 39 TARDIS, which served as his rooms at St. Cedd's College, Cambridge. This TARDIS model could hold another TARDIS within its force field and create a bridge between the two to walk through.

Type 39 TARDISes were capable of interfering in an individual's time stream. (DW: Shada)