Sonic Pen (The Magician's Apprentice)

The sonic pen was a device used by the Detective that functioned in a similar fashion to the Doctor's sonic screwdriver. It a plastic handle, the top and bottom were metallic, and had a brass tip that nested a red diode at the end, along with the Seal of Rassilon on the handle (TV: The Magician's Apprentice).

A psychic interface allowed its user to point it at a target and think of the function they wanted, instead of "settings" (TV: Under the Lake, The Girl Who Died). Having been mentioned to be more than sonic, (TV: Under the Lake) this pen also used digital technology to create a sonic wave, projected into the form of pulsing squares of red light, which could cut through thick walls along with a reverse function which could replace the removed chunk of material afterwards, and shot beams of red energy in the shape of sonic waves. It had a frequency dial to turn/tune to different frequencies in order to track other species, which the Detective forgot about when he needed it. (TV: The Zygon Invasion).