Dōtei

Dōtei (瞳偵,; English TV "Visual Gadgetry"; Literally meaning "Eye Spy") are perception enhancing tools, achieving various effects. They originate from the Minamoto clan, traditionally used to assist their kyūjutsu.

Background
They were created early on by the Minamoto clan to aide in their kyūjutsu and continually renovated. By the time of the Fourth Shinobi World War lesser versions of dōtei, similar to the early versions used by the Minamoto, have become accessible to the ninja world.

Appearance
Dōtei take on varying appearances, such as the eye scope used by Akatsuki member Deidara, which was small enough to be hidden under his hair. The most common version used by the Minamoto are in the form of shooting glasses, with diverse colours of glass and frames. Others use goggles, or combined with forehead protectors as visors.