Sonic lantern
From Tardis Wiki, the free Doctor Who reference
Sonic lanterns were small, yellow devices used by the Silurians. They produced irritating noises which could be used to corral dinosaurs in place.
When a Tyrannosaurus rex was accidentally brought to 1890s London, Madame Vastra gave the police force a sack of sonic lanterns to keep the dinosaur from wandering off. While the Twelfth Doctor was drifting in and out of post-regeneration confusion, he claimed the sonic lanterns were giving the dinosaur headaches. (TV: Deep Breath)
Behind the scenes
In the stage directions from the script of "Deep Breath", this type of lantern was simply physically described as a "high-tech lantern". Also, the script had Madame Vastra ask Strax to layout the lanterns, whereas she asks the police force to do so in the episode.
