Sonic umbrella

owned a sonic umbrella.

She used it aboard a Mondasian colony ship during the Battle of Floor 0507. The activation controls were located at the handle end opposite the emitter at the tip. Missy had a tendency to dance with it when hearing music. It had multiple uses, namely how Missy used her umbrella to locate and call up a lift on board the Mondasian colony ship, (TV: World Enough and Time / The Doctor Falls) locate the hidden lifts and shuttles found on Floor 0507, lock said lifts to stay on the desired floor, close a metal door several feet away and could combine with the Twelfth Doctor's sonic screwdriver to create a barrier to hold a fully evolved Cyberman back while (using his laser screwdriver) and a cyber-converted Bill Potts disabled it. The umbrella could also be used as an effective melee weapon; Missy used it to strike the Doctor to the floor shortly after he gained an advantage over her younger self, and to briefly knock the Master out with a blow to the head. (TV: The Doctor Falls)

In some instances, it sounded like a sonic screwdriver (TV: World Enough and Time / The Doctor Falls) but in some others it's sound resembled a laser screwdriver. (AUDIO: Day of the Master)

Her successor gave up using both this tool and the multipurpose device in favour of returning to wielding a tissue compression eliminator.

Behind the scenes
According to the BBC art concept, the tip of the umbrella was supposed to look like a red version of the Twelfth Doctor's screwdriver lighting.