The Twin Eye Spectacles are discovered as set of two pairs of glasses, round lenses compiled in a thin metal frame. Seemingly they are completely normal, except for the adjustable lens on one side (a different side for each pair) which is reminiscent of a lens a jeweller might have attached to their spectacles. Upon wearing these glasses it becomes apparent that the lenses are simple glass and have no effect on the vision of its wearer. However, placing the adjustable lens in front of one's eye allows them to see through that lens into the other pair. This allows them to see whatever is directly in front of the other pair of Twin Eye Spectacles. This effect takes place regardless of distance as long as both pairs are in working condition. If one pair is destroyed the other pair becomes completely mundane and the adjustable lens is revealed to be plain glass, just like the regular lenses. A character who requires glasses for sight will likely be unable to use these spectacles as they will lose the corrective benefits their normal glasses provide. However, if a character who normally wears glasses tries to done these spectacles I would recommend giving them a penalty to perception checks (or equivalent) and other sight related challenges. Darkvision or other abilities that affect the vision of the character do not apply while looking through the Twin Eye Spectacles.
Twin Eye Spectacles
Ever wanted to see through someone else's eyes. Well now you can!