This brass monocle has a simple design with a crystal lens. Unlike a normal monocle, however, it does not adjust you vision. it has a small, spherical emerald  embedded in brass housing of the crystal lens.

The wearer of this monocle gains a +2 to their passive perception as long as they are attuned to it.

Spy VS. Spy- Whenever the wearer of this monocle would be scryed upon, the small emerald will glow slightly, alerting the wearer that they are being scryed on. If the scry is successful, the wearer of this monocle may then cast Scrying,  without needing any of its components, upon the individual who originally cast the spell with a WIS DC of 18. This ability may only be used three(3) times a day.