Time Converter

The Time Converter was a device possessed by Sarah Jane Smith which allowed the detection, opening and closing of time fissures in areas where the Web of Time remained thin. Fearing that she might use it to alter her timeline as she had recently, Sarah Jane destroyed it. (SJA: The Temptation of Sarah Jane Smith)

It had some functional similarities to the Doctor's timey-wimey detector (and similar device) and functioned like a small scale Rift Manipulator.

Behind the Scenes

The Sarah Jane Adventures website describes it origin as unknown and says that the Converter "[could] manipulate time energy in order to create time fissures between fixed points in time. But be careful; these time fissures are very temperamental and could shut at any time!