Hero illuminating medical device used by The Doctor to repair Seven Of Nine's cortical array in sixth season opener Equinox part II. Also seen earlier in fourth season episode Retrospect, where The Doctor found this 'microcaliper' in Entharan weapons merchant Kovin's lab. I guess the doc borrowed and repurposed the device for his own use.
Aluminum with acrylic tip which lights up when extended by a plunger.
From Profiles In History.
By Prop'er Effects.
