Let's look at some techniques used by spies, only a few decades ago.
Coin from the arsenal of a cache inside the KGB.
The gun in the arsenal of the KGB mounted in the chuck of lipstick.
Compass in the form of a pair of buttons. To navigate on such a compass, it is necessary to set the halves at each other.
A bomb disguised as a canteen.
The bomb, disguised as a piece of coal. Set for applying camouflage paint. From the CIA arsenal of the twentieth century.
The camera is disguised as a button.