|First Appearance||Dark Harvest|
When Dib unwraps the package, he puts them on and uses them to see what Zim's organs look like, much to his amazement, as he calls the unknown organs "incredible". The goggles label Zim's alien Squeedly-Spooch as "unknown".
The X-Scope is essentially a set of X-ray goggles which displays and identifies particular organs to the viewer. As seen in the only episode it appears in, the X-Scope is also capable of identifying foreign objects such as rulers, milk cartons, a Game Slave, and cats.
Dib only uses the X-Scope in "Dark Harvest". It is unknown what happens to it afterwards.