Type 44

The  was a kind of TARDIS that was slightly more advanced than the Type 40. According to the Third Doctor, this was the first model to be fitted with a charged vacuum resonator, which his own TARDIS lacked when he and the Master were trying to reach the Sild. (PROSE: Harvest of Time)

According to a single source, the Doctor's TARDIS was a Type-44 capsule. (GAME: An Unlikely Heist)