X-Ray Specs

A cheap magic item sometimes found in the City, X-Ray Spectacles are apparently mass-produced and sold in the back of lurid pulps and comics.  The item is sold for as little as a single Union dollar--with good reason, as 90% or more are fakes whose only magical power is to appear faintly magical, distort one's vision slightly when wearing them, and cause headaches.  The real X-Ray Spectacles (sold from identical ads as the fake ones) are identical cardboard glasses (not unlike old fashion 3-D glasses in our world ) with swirling, swifting patterns in the thin, plastic lens.

Real X-Ray Spectacles confer the power to see through solid matter, though things seen are not in color and somewhat hazy.  This is uneffected by illumination.  Vision range is 20 feet, and the viewer can see through 1 foot or so of most materials with concentration, though only 1 inch of solid metal, with a round's concentration.  Without concetration, the wearer can see through no more than a quarter of an inch, which mainly makes them good for seeing through clothes.  Even without concetration, they see through illusions of most types.
The unknown manufactures of the spectacles make a shoddy product which extraplanar energies.  Repeated use or extended wear of the spectacles (more than once a day, or for more than 2 mintues) requires a saving throw or else suffering 1 point reduction in Constitution.  Every day the spectacles are in a person's possession (and not kept in a lead-lined or magically warded container) has a cumulative 5% chance of attracting the unwanted attention of malign astral entities.