Verron puzzle box

Two puzzle boxes with special powers were given to Sarah Jane Smith and Andrea Yates.

Sarah Jane's puzzle box
Sarah Jane was given hers by a Verron soothsayer. It would protect its holder from the power of the Trickster, even if the Trickster's machinations had created an entire alternate timeline. (TV: Whatever Happened to Sarah Jane?, TV: The Temptation of Sarah Jane Smith) It protected Maria Jackson and later Alan Jackson during the Trickster's attempt to destroy Earth by killing Sarah Jane as a child. (TV: Whatever Happened to Sarah Jane?) Later, it alerted Rani Chandra and Clyde Langer to the renewed threat of the Trickster, and protected them and their memories from the switch to a timeline where the Trickster conquered Earth, having manifested in 1951. The box continued to protect Clyde and Rani from Krislok, a Graske working as the Trickster's agent. In exchange for helping them defeat the Trickster, Clyde gave the Graske the box to protect him should the Trickster ever seek revenge. (TV: The Temptation of Sarah Jane Smith)

Andrea's puzzle box
The Trickster himself gave one to Andrea Yates in 1964 to enable her to forget that she had voluntarily swapped places with Sarah Jane Smith, thus causing Sarah Jane's death. It was used by Andrea Yates to call the Trickster after Maria Jackson had (from Andrea Yates' viewpoint) begun to remember the existence of Sarah Jane Smith. (TV: Whatever Happened to Sarah Jane?)

Others
A Verron puzzle box resided within the remembered TARDIS, with Clyde accidently sitting on it when he took a seat and fiddling with it as he talked to Jo Jones. (TV: The Three Doctors)