Vortex manipulator

A vortex manipulator was a form of basic time machine developed by the Time Agency of the 51st century. Although it was generally used by the Agency, the Family of Blood stole one to follow the Doctor around the universe. (DW: Human Nature)

The Doctor considered it very primitive compared to a TARDIS, describing his TARDIS as a "sports car" to Jack Harkness's "space hopper".

A vortex manipulator had the apprearance of a brown sweatband worn on the wrist. (DW: Utopia)